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{| class="infobox" style="width: 20em;"
|-
! colspan="2" style="text-align:center; font:10em verdana; background:#ccc;"| 7
|-
| colspan="2" | {{numbers (digits)}}
|-
| [[Cardinal number|Cardinal]]
| 7 <br /> seven
|-
| [[Ordinal number (linguistics)|Ordinal]]
| 7th <br /> seventh
|-
| [[Numeral system]]
| [[septenary]]
|-
| [[Factorization]]
| [[prime number|prime]]
|-
| [[Divisor]]s
| 1, 7
|-
| [[Greek numeral]]
| [[zeta|Z]], ζ
|-
| [[Roman numeral]]
| VII
|-
| Roman numeral (Unicode)
| Ⅶ, ⅶ
|-
| [[Amharic language|Amharic]] || <font style="font-size:100%;">፯</font>
|-
| [[Arabic]] || <font style="font-size:150%;">٧,7</font>
|-
| [[Persian language|Persian]] || <font style="font-size:150%;">٧ - هفت</font>
|-
| [[Bengali language|Bengali]] || <font style="font-size:150%;">৭</font>
|-
| [[Chinese numeral]] || 七(qi)
|-
| [[Devanāgarī]] || <font style="font-size:150%;">७</font> (saat)
|-
| [[Tamil language|Tamil]] || <font style="font-size:150%;">௭</font>
|-
| [[Hebrew (language)|Hebrew]] || <font style="font-size:150%;">ז</font> (Zayin)
|-
| [[Khmer numerals|Khmer]] || ៧
|-
| [[Thai numerals|Thai]] || ๗
|-
| [[numerical prefix|prefixes]]
| [[wikt:hepta-|hepta-]]/[[wikt:hept-|hept-]] (from [[Greek language|Greek]])
[[wikt:septua-|septua-]] (from [[Latin]])
|-
| [[Binary numeral system|Binary]]
| 111
|-
| [[Octal]]
| 7
|-
| [[Duodecimal]]
| 7
|-
| [[Hexadecimal]]
| 7
|}
'''7''' ('''seven''';{{IPAc-en|s|ɛ|v|ɨ|n|}}) is the [[natural number]] following {{num|6}} and preceding {{num|8}}.

==Mathematics==
* Seven, the fourth [[prime number]], is not only a [[Mersenne prime]] (since 2<sup>3</sup>&nbsp;−&nbsp;1&nbsp;=&nbsp;7) but also a [[double Mersenne prime]] since the exponent, 3, is itself a Mersenne prime. It is also a [[Newman–Shanks–Williams prime]], a [[Woodall prime]], a [[factorial prime]], a [[lucky prime]], a [[happy number]], a [[safe prime]] and the fourth [[Heegner number]].
* Seven is the lowest number that cannot be represented as the sum of the squares of three integers. (See [[Lagrange's four-square theorem#Historical development]].)
* Seven is the [[aliquot sum]] of one number, the [[cubic number]] {{num|8}} and is the base of the 7-aliquot tree.
* ''n'' = 7 is the first natural number for which the next statement does not hold: "Two [[nilpotent]] [[endomorphism]]s from '''C'''<sup>''n''</sup> with the same [[minimal polynomial]] and the same rank are similar."
* 7 is the only dimension, besides the familiar 3, in which a vector [[cross product]] can [[seven-dimensional cross product|be defined]].
* [[999999 (number)|999,999]] divided by 7 is exactly [[142857 (number)|142,857]]. Therefore, when a [[vulgar fraction]] with 7 in the [[denominator]] is converted to a [[decimal]] expansion, the result has the same six-[[numerical digit|digit]] repeating sequence after the decimal point, but the sequence can start with any of those six digits.<ref>Bryan Bunch, ''The Kingdom of Infinite Number''. New York: W. H. Freeman & Company (2000): 82</ref> For example, 1/7&nbsp;=&nbsp;0.142&nbsp;857&nbsp;142.... and 2/7&nbsp;=&nbsp;0.285&nbsp;714&nbsp;285...
In fact, if one sorts the digits in the number 142857 in ascending order, 124578, it is possible to know from which of the digits the decimal part of the number is going to begin with. The remainder of dividing any number by 7 will give the position in the sequence 124578 that the decimal part of the resulting number will start. For example, 628/7= 89 + 5/7; here 5 is the remainder, and would correspond to number 7 in the ranking of the ascending sequence. So in this case, 628/7 = 89,714285... Another example, 5238/7 = 748 + 2/7, hence the remainder is 2, and this corresponds to number 2 in the sequence. In this case, 5238/7 = 748,285714...
* A seven-sided shape is a [[heptagon]]. The regular ''n''-gons for ''n'' ≤ 6 can be constructed by [[compass and straightedge]] alone, but the regular heptagon cannot. [[Figurate number]]s representing heptagons (including seven) are called [[heptagonal number]]s. Seven is also a [[centered hexagonal number]].
* There are seven [[frieze group]]s, the [[group (mathematics)|groups]] consisting of [[symmetry group|symmetries]] of the plane whose group of [[translation (mathematics)|translations]] is [[isomorphic]] to the group of [[integer]]s.
* There are seven fundamental types of [[catastrophe theory|catastrophes]].
* Seven is the sum of any two opposite sides on a standard six-sided die. When rolling two standard six-sided [[dice]], seven has a 6 in {{num|36}} (or 1/6) probability of being rolled (1–6, 6–1, 2–5, 5–2, 3–4, or 4–3), the greatest of any number.
* The [[Millennium Prize Problems]] are seven problems in [[mathematics]] that were stated by the [[Clay Mathematics Institute]] in 2000. Currently, six of the problems remain [[unsolved problems in mathematics|unsolved]].

===Numeral systems===
{| class="wikitable"
! [[Radix|Base]]
! [[Numeral system]]
!
|-
| 2 || [[binary numeral system|binary]] || 111
|-
| 3 || [[ternary numeral system|ternary]] || 21
|-
| 4 || [[quaternary numeral system|quaternary]] || 13
|-
| 5 || [[quinary]] || 12
|-
| 6 || [[senary]] || 11
|-
| 7 || [[septenary]] || 10
|-
| colspan="2" | over 7 ([[octal]], [[decimal]], etc.)
| 7
|}

In quaternary, 7 is the smallest prime with a composite sum of digits.

===Basic calculations===
{|class="wikitable" style="text-align: center; background: white"
|-
!width="105px"|[[Multiplication]]
!1
!2
!3
!4
!5
!6
!7
!8
!9
!10
!11
!12
!13
!14
!15
!16
!17
!18
!19
!20
!21
!22
!23
!24
!25
!50
!100
!1000
|-
|7 × ''x''
|'''7'''
|{{num|14}}
|{{num|21}}
|{{num|28}}
|{{num|35}}
|{{num|42}}
|{{num|49}}
|{{num|56}}
|{{num|63}}
|{{num|70}}
|{{num|77}}
|{{num|84}}
|{{num|91}}
|{{num|98}}
|{{num|105}}
|{{num|112}}
|{{num|119}}
|{{num|126}}
|{{num|133}}
|{{num|140}}
|{{num|147}}
|{{num|154}}
|{{num|161}}
|{{num|168}}
|{{num|175}}
|{{num|350}}
|{{num|700}}
|{{num|7000}}
|}

{|class="wikitable" style="text-align: center; background: white"
|-
!width="105px" rowspan="2"|[[Division (mathematics)|Division]]
!1
!2
!3
!4
!5
!6
!7
!8
!9
!10
|-
!11
!12
!13
!14
!15
|
|
|
|
|
|-
|rowspan="2"|7 ÷ ''x''
|'''7'''
|3.5
|2.<span style="text-decoration:overline">3</span>
|1.75
|1.4
|1.1<span style="text-decoration:overline">6</span>
|1
|0.875
|0.<span style="text-decoration:overline">7</span>
|0.7
|-
|0.<span style="text-decoration:overline">63</span>
|0.58<span style="text-decoration:overline">3</span>
|0.<span style="text-decoration:overline">538461</span>
|0.5
|0.4<span style="text-decoration:overline">6</span>
|
|
|
|
|
|-
|rowspan="2"|''x'' ÷ 7
|0.<span style="text-decoration:overline">142857</span>
|0.<span style="text-decoration:overline">285714</span>
|0.<span style="text-decoration:overline">428571</span>
|0.<span style="text-decoration:overline">571428</span>
|0.<span style="text-decoration:overline">714285</span>
|0.<span style="text-decoration:overline">857142</span>
|1
|1.<span style="text-decoration:overline">142857</span>
|1.<span style="text-decoration:overline">285714</span>
|1.<span style="text-decoration:overline">428571</span>
|-
|1.<span style="text-decoration:overline">571428</span>
|1.<span style="text-decoration:overline">714285</span>
|1.<span style="text-decoration:overline">857142</span>
|{{num|2}}
|2.<span style="text-decoration:overline">142857</span>
|
|
|
|
|
|}

{|class="wikitable" style="text-align: center; background: white"
|-
!width="105px"|[[Exponentiation]]
!1
!2
!3
!4
!5
!6
!7
!8
!9
!10
!width="5px"|
!11
!12
!13
|-
|7<sup>''x''</sup>
|'''7'''
|49
|{{num|343}}
|2401
|16807
|117649
|823543
|5764801
|40353607
|282475249
!
|1977326743
|13841287201
|96889010407
|-
|''x''<sup>7</sup>
|1
|{{num|128}}
|2187
|16384
|78125
|279936
|823543
|2097152
|4782969
|{{num|10000000}}
!
|19487171
|35831808
|62748517
|}

{|class="wikitable" style="text-align: center; background: white"
!rowspan="2" width="105px"|[[Radix]]
!1
!5
!10
!15
!20
!25
!30
<!--
!35
-->
!40
<!--
!45
-->
!50
!60
!70
!80
!90
!100
|-
!110
!120
!130
!140
!150
<!--
!160
!170
!180
!190
-->
!200
!250
!500
!1000
!10000
!100000
!1000000
|
|
|-
|rowspan="2"|''x''<sub>7</sub>
|1
|5
|13<sub>7</sub>
|21<sub>7</sub>
|26<sub>7</sub>
|34<sub>7</sub>
|42<sub>7</sub>
<!--
|50<sub>7</sub>
-->
|55<sub>7</sub>
<!--
|63<sub>7</sub>
-->
|101<sub>7</sub>
|114<sub>7</sub>
|130<sub>7</sub>
|143<sub>7</sub>
|156<sub>7</sub>
|202<sub>7</sub>
|-
|215<sub>7</sub>
|231<sub>7</sub>
|244<sub>7</sub>
|260<sub>7</sub>
|303<sub>7</sub>
<!--
|316<sub>7</sub>
|322<sub>7</sub>
|345<sub>7</sub>
|361<sub>7</sub>
-->
|404<sub>7</sub>
|505<sub>7</sub>
|1313<sub>7</sub>
|2626<sub>7</sub>
|41104<sub>7</sub>
|564355<sub>7</sub>
|11333311<sub>7</sub>
|
|}

==Evolution of the glyph==
[[File:SevenGlyph.svg|200px]]<br>
In the beginning, various [[Hindu]]s wrote 7 more or less in one stroke as a curve that looks like an [[uppercase]] [[J]] vertically inverted. The western Ghubar Arabs' main contribution was to make the longer line diagonal rather than straight, though they showed some tendencies to making the [[grapheme|character]] more rectilinear. The eastern [[Arab]]s developed the character from a 6-look-alike into an uppercase V-look-alike. Both modern Arab forms influenced the European form, a two-stroke character consisting of a horizontal upper line joined at its right to a line going down to the bottom left corner, a line that is slightly curved in some font variants. As is the case with the [[Europe]]an glyph, the Cham and Khmer glyph for 7 also evolved to look like their glyph for 1, though in a different way, so they were also concerned with making their 7 more different. For the Khmer this often involved adding a horizontal line above the glyph.<ref>Georges Ifrah, ''The Universal History of Numbers: From Prehistory to the Invention of the Computer'' transl. David Bellos et al. London: The Harvill Press (1998): 395, Fig. 24.67</ref> This is analogous to the horizontal stroke through the middle that is sometimes used in handwriting in the Western world but which is almost never used in computer fonts. This horizontal stroke is, however, important to distinguish the glyph for seven from the glyph for [[1 (number)|one]] in writings that use a long upstroke in the glyph for 1.

[[File:sevens.svg|right|100px]]
[[File:Digital77.svg|left|50px]]
On the [[seven-segment display]]s of pocket calculators and digital watches, 7 is the number with the most common glyph variation (0, 6 and 9 also have variant glyphs). Most calculators use three line segments, but on [[Sharp Corporation|Sharp]], [[Casio]], and a few other brands of calculators, 7 is written with four line segments because, in Japan and Korea, 7 is written as ① in the illustration to the right.

While the shape of the 7 character has an [[ascender (typography)|ascender]] in most modern [[typeface]]s, in typefaces with [[text figures]] the character usually has a [[descender]], as, for example, in [[File:TextFigs078.svg|40px]].

[[File:Hand Written 7.svg|left|50px]]Most people in Europe, Latin America, and [[New England]]{{citation needed|date=March 2011}} write 7 with a line in the middle ("<strike>7</strike><!--any Unicode?-->"), sometimes with the top line crooked. The line through the middle is useful to clearly differentiate the character from the number one, as these can appear similar when written in certain styles of handwriting. This glyph is used in official handwriting rules for primary school in Russia, Ukraine and other Slavic countries.<ref>[http://www.adu.by/modules.php?name=News&file=article&sid=858 "Education writing numerals in grade 1."](Russian)</ref>

==Automotive and transportation==
* [[7 (New York City Subway service)]], a service of the New York City Subway
* [[BMW 7 Series]], flagship luxury vehicle from German automobile manufacturer, [[BMW]].
* The [[Lotus Seven]], a kit car produced by Lotus

==Classical world==
===Classical antiquity===
* [[Seven against Thebes]]
* [[Seven Kings of Rome]]
* [[Seven Emperors]] (and period; [[Rome]], history)
** [[Julius Caesar]], [[Augustus]], [[Galba]], [[Hadrian]], [[Nerva]], [[Sallust]], [[Vespasian]]
* [[Seven hills of Istanbul|Seven hills of Constantinople]]
* [[Seven hills of Rome]]
* [[Seven Liberal Arts]]
* [[Seven Sages of the Bamboo Grove]] in China
* [[Seven Sages of Greece]]
* ''[[Seven Wise Masters]]'', a cycle of medieval stories
* [[Seven Wonders of the ancient world]]

==Commerce and business==
* The [[fifty pence (British decimal coin)|British fifty pence coin]] has [[heptagon|7 sides]]
* [[7-Eleven]] is the trading name of a chain of convenience stores based in the U.S.
* [[Seven 7 (clothing)|Seven Jeans]], also known as ''Seven '7' for all Mankind'', a brand of designer jeans.

==Food and beverages==
* [[7UP]] is the name of a popular soft drink.

==Media and entertainment==
===Film===
====Characters====
* [[James Bond]]'s secret agent number is 007
* The [[anime]] ''[[Elfen Lied]]'' includes a character called Nana (Japanese for 7)

====Titles====
* The [[1925 in film|1925]] film ''[[Seven Chances]]'' starring [[Buster Keaton]]
* In the [[Disney]] film [[Snow White and the Seven Dwarfs (1937 film)|''Snow White and the Seven Dwarfs'' (1937)]]
* The [[1940 in film|1940]] film ''[[Seven Sinners (1940 film)|Seven Sinners]]'' directed by [[Tay Garnett]], starring [[Marlene Dietrich]]
* The musical film ''[[Seven Brides for Seven Brothers (film)|Seven Brides for Seven Brothers]]'' (1954)
* The [[1954 in film|1954]] ''[[Seven Samurai]]'' by [[Akira Kurosawa]] starring [[Toshirō Mifune]]
* The [[Marilyn Monroe]] film ''[[The Seven Year Itch]]'' (1955) which is famous for the white dress blowing up
* The [[Sweden|Swedish]] [[film]] ''[[The Seventh Seal]]'' (1957) directed by [[Ingmar Bergman]]
* The [[1960 in film|1960]] American [[western (genre)|western film]] ''[[The Magnificent Seven]]'' starring [[Yul Brynner]]
* The 1964 film, "7 Faces of Dr. Lao" starring [[Tony Randall]].
* The movie ''[[The Seventh Sign]]'', directed in 1988 by [[Carl Schultz]] and starring [[Jürgen Prochnow]] and [[Demi Moore]]
* The movie ''[[Se7en (film)|Se7en]]'', directed in 1995 by [[David Fincher]] and starring [[Brad Pitt]] and [[Morgan Freeman]]
* The film ''[[Lucky Number Slevin]]'', directed in 2006 by [[Paul McGuigan (filmmaker)|Paul McGuigan]] starring [[Josh Hartnett]] and [[Morgan Freeman]]
* The [[1997 in film|1997]] film ''[[Seven Years in Tibet (1997 film)|Seven Years in Tibet]]'' directed by [[Jean-Jacques Annaud]]
* The [[2008 in film|2008]] film ''[[Seven Pounds]]'' starring [[Will Smith]]

===Games (other than video games)===
* [[Lotto Super 7]], a Canadian-lottery game that had its final drawing September 18, 2009.
* [[Sevens (card game)|Sevens]], a card game

===Literature===
* ''[[As You Like It]]'' by [[William Shakespeare]]'s contains Shakespeare's 7 Ages of Man theory.
* In ''[[Beloved (novel)]]'' by [[Toni Morrison]] the number seven seems to have recurring significance, Beloved has seven letters, 124 adds up to seven, each chapter begins on a number containing seven, and the second chapter contains seven parts.
* The original British version of [[Anthony Burgess]]' novel ''[[A Clockwork Orange]]'' is split in to three sections of seven chapters.
* In the first of the three ''[[Deltora Quest]]'' series of books by [[Emily Rodda]], the protagonist must collect the seven gems of the fabled Belt of Deltora: topaz, ruby, opal, lapis lazuli, emerald, amethyst, and diamond. Each of the seven gems are guarded by one of seven guardians located in one of the seven locations around Deltora: The Forests of Silence, Lake of Tears, City of the Rats, The Shifting Sands, Dread Mountain, Maze of the Beast, and Valley of the Lost.
* The manga ''[[Eureka Seven]]'', based on the anime series
* In ''[[Fist of the North Star]]'' ([[Hokuto no Ken]]), the main character, [[Kenshiro]], is also known as "the man with seven wounds" for the seven scars on his body in the shape of the [[Big Dipper]].
* In the ''[[Fushigi Yuugi]]'' manga series, the four beast gods each have seven warriors, the Genbu Seven, the Byakko Seven, the Seiryuu Seven, and the Suzaku Seven.
* In the ''[[Harry Potter]]'' series of novels by [[J.K. Rowling]], seven is said to be the most powerfully [[Magic (Harry Potter)|magical]] number. There are a number of references to seven in ''Harry Potter'': there are a total of seven books in the series; [[Ginny Weasley]] is the seventh child and only daughter of the Weasley family; [[Harry Potter (character)|Harry Potter]] was born in July, the seventh month of the year; Wizarding students must complete seven years of school at [[Hogwarts]]; There are seven secret passages in [[Hogwarts]]; Seven is also the number on the back of [[Harry Potter's]] Quidditch robes ([[Harry Potter and the Prisoner of Azkaban (film)|''Prisoner of Azkaban'' movie)]]. In [[Quidditch]] each team consists of seven players. Chapter four of [[Harry Potter and the Deathly Hallows|Book 7]] is titled "The Seven Potters". Lord Voldemort succeeded in splitting his soul into seven parts.
* In the ''[[InuYasha]]'' series, the [[Shichinintai]] are, as their name says, a band of seven mercenaries.
* The Seven Rings of the [[Vongola Family]] in ''[[Katekyo Hitman Reborn]]'': Sky, Storm, Rain, Sun, Thunder, Mist, and Cloud.
* In ''[[The Lost Years of Merlin]]'' series, a book is titled "The Seven Songs of Merlin"
* The character 7 (Nana) and the organization Septimal Moon in [[Loveless (manga)|''Loveless'' (manga)]]
* In the "[[Nana (manga)|Nana]]'' manga series, there are many recurrent instances of the number seven ("nana" is the [[Japanese numerals|Japanese numeral]] for the English "seven"), including the name of both main characters.
* Team 7 consists of the main characters in ''[[Naruto]]'': [[Naruto Uzumaki]], [[Sasuke Uchiha]], [[Kakashi Hatake]], and [[Sakura Haruno]]. Later in the series, [[List of Naruto characters|Sai]] joined team 7 after Sasuke left [[Konohagakure]].
* In the ''[[One Piece]]'' series, the [[Shichibukai]] (literally, "Seven Military Seas", known in the English versions as the "Seven Warlords of the Sea") are seven powerful pirates who [[privateer|work for the government]].
* ''The Saga of Seven Suns'', a series of seven novels by [[Kevin J. Anderson]].
* In [[Neil Gaiman]]'s ''[[The Sandman (Vertigo)|Sandman]]'' series, there are 7 Endless: Destiny, Death, Dream, Destruction, Despair, Desire and Delirium.
* ''[[The Secret Seven]]'', name of a children's adventure book by [[Enid Blyton]]
* In the ''[[Septimus Heap]]'' series, Septimus Is the seventh son of a seventh son, 7 is believed to be the most magykal number. There will also be 7 books in the series, along with many other things relating to the number 7.
* [[Aleksis Kivi]]'s "[[Seven Brothers]]", the most famous book of Finnish literature
* ''[[The Seven Dials Mystery]]'' by [[Agatha Christie]]
* ''[[The Seven Habits of Highly Effective People]]'', a book by [[Stephen Covey]]
* [[Seven Pillars of Wisdom]], a book written by [[T.E. Lawrence]]
* The book ''[[Seven Years in Tibet]]''
* In ''[[The Silmarillion]]'', also a Tolkien work, there are seven Lords of the [[Vala (Middle-earth)|Valar]], and seven Ladies of the Valar; [[Fëanor]], a central character, has seven sons: [[Maedhros]], [[Maglor]], [[Celegorm]], [[Curufin]], [[Caranthir]], [[Amrod]], and [[Amras]].
* In George R.R. Martin's ''[[A Song of Ice and Fire]]'', seven gods, the Mother, the Father, the Warrior, the Crone, the Smith, the Maiden, and the Stranger, are worshipped in the land of [[Westeros]], which is made up of seven former kingdoms and often called the Seven Kingdoms. The Seven are the primary deities of Westeros.
* In [[W.E.B. Du Bois]]'s book ''The Souls of Black Folk'', he refers to "the Negro" as "the seventh son".
* In ''[[The Tales of Alvin Maker]]'', an alternate history fantasy series by [[Orson Scott Card]], seventh sons are imbued with special powers, referred to as "knacks", over the physical world. The powers of a seventh son of a seventh son, the birthright of the series' main character, Alvin Smith, are especially pronounced. Men who wield these powers to create are referred to as "Makers."
* In ''[[Toaru Majutsu no Index]]'', there are a total of seven Level 5 ESPers: Accelerator, Kakine teitoku, Misaka Mikoto, Mugino Shizuri, The Queen of Tokiwadai, an unknown ESPer and Sogiita Gunha.
* In ''[[The Two Towers]]'', the second volume of [[J.R.R. Tolkien]]'s ''[[The Lord of the Rings]]'', the following poem appears: "Tall ships and tall kings/Three times three/What brought they from the foundered land/Over the flowing sea?/Seven stars and seven stones/And one white tree." The "foundered land" is [[Númenor]], and the "Seven Stars" are unknown, but they may refer to a constellation, the Sickle of the Valar. The Seven Stones are the ''[[palantír]]i'', the seeing-stones. The number seven was also significant to Dwarvish culture as portrayed by Tolkien: there were seven fathers of the Dwarves (as recounted in ''The Silmarillion'') and the [[Dwarf (Middle-earth)|Dwarves]] were later given seven rings by Sauron (according to ''The Lord of the Rings'').
* David Eastis authored two books about the popular number seven both with the title "7".
* Jackie Leo wrote "Seven".

===Music===
* The number of notes in the traditional Western Major Scale
* In music, the Roman numeral vii is the [[leading tone]] (vii{{music|dimdeg}}) or [[subtonic]] (VII) [[scale degree]], [[chord (music)|chord]] ([[leading-tone seventh chord]] or [[secondary leading-tone chord]]), or [[diatonic function]], when distinguished V = major and v = minor.
* The original diameter in inches of the 45rpm format [[gramophone record]].
* There are seven musicians in a [[septet]] or a septuor.
* The number 7 appears on several metal band albums, such as Iron Maiden's ''[[Seventh Son of a Seventh Son]]'' and Helloween's ''[[Keeper of the Seven Keys]]''.

===Sports===
* In the [[National Hockey League|NHL]], [[Major League Baseball|MLB]], and [[National Basketball Association|NBA]], the maximum number of games played in a playoff series
* The jersey number 7 has been retired by several [[Major professional sports leagues in the United States and Canada|North American sports]] teams in honor of past playing greats:
** [[Major League Baseball]]
*** The [[Houston Astros]], for likely future [[National Baseball Hall of Fame and Museum|Hall of Famer]] [[Craig Biggio]].
*** The [[New York Yankees]], for Hall of Famer [[Mickey Mantle]].
** [[National Football League]]:
*** The [[Chicago Bears]], for [[Pro Football Hall of Fame|Hall of Fame]] player, coach, and owner [[George Halas]].
*** The [[Denver Broncos]], for Hall of Famer [[John Elway]].
*** The [[Detroit Lions]], for Hall of Famer [[Dutch Clark]].
*** The [[New York Giants]], for Hall of Famer [[Mel Hein]].
*** The [[St. Louis Rams]], for Hall of Famer [[Bob Waterfield]], who played for the franchise when it was in Los Angeles.
** [[National Basketball Association]]
*** The [[Cleveland Cavaliers]], for [[Bingo Smith]].
*** The [[New Orleans Hornets]], for [[Basketball Hall of Fame|Hall of Famer]] [[Pete Maravich]]. He died in January 1988, before the franchise began as the Charlotte Hornets, but his number was retired based on his years in the city with the New Orleans Jazz.
*** The [[Phoenix Suns]], for [[Kevin Johnson]].
*** The [[Utah Jazz]], also for Maravich. He briefly played with the team while it was in Utah, and played five seasons with the team in its previous location of New Orleans.
** [[National Hockey League]]
*** The [[Boston Bruins]], for [[Hockey Hall of Fame|Hall of Famer]] [[Phil Esposito]].
*** The [[Buffalo Sabres]], for [[Rick Martin]].
*** The [[Dallas Stars]], for [[Neal Broten]].
*** The [[Detroit Red Wings]], for Hall of Famer [[Ted Lindsay]].
*** The [[Edmonton Oilers]], for Hall of Famer [[Paul Coffey]].
*** The [[New York Rangers]], for Hall of Famer [[Rod Gilbert]].
*** The [[Philadelphia Flyers]], for Hall of Famer [[Bill Barber]].
*** The [[Washington Capitals]], for [[Yvon Labre]].
*** The [[Toronto Maple Leafs]] have a policy of not retiring numbers unless the player honoured either died or suffered a career-ending incident while a member of the team. Other players whose numbers would otherwise be retired instead have their numbers enshrined by the team as "Honoured Numbers", which remain in circulation for future players. The number 7 is currently honoured for Hall of Famers [[King Clancy]] and [[Tim Horton]].

;Baseball
* In high-school [[baseball]] a regulation game lasts seven [[innings]].
* In [[baseball]], the [[Seventh-inning stretch|7th Inning stretch]] attributed to the 27th U.S. President, William Howard Taft
* In scoring [[baseball]], seven represents the [[left fielder]]'s position

;Football and soccer
* In [[association football]] the forward or winger tradiationally wears the number 7
* In [[American football|American]] and [[Canadian football]], the minimum number of players who, by rule, must be lined up at the line of scrimmage on offense (otherwise the team commits the penalty of [[illegal formation]])

;Frisbee and Ultimate Frisbee
* In [[Ultimate (sport)|Ultimate Frisbee]], the number of players on the field for each team

;Handball
* In [[team handball]], the number of players on each team including the [[goalkeeper]]

;Motor sports
* In [[motorcycling]], the racing number for the late British World Champion [[Barry Sheene]]
* In [[NASCAR Nationwide Series]], the racing number is for driver [[Danica Patrick]]
* In [[Indy Car Series]], the racing number is for driver [[Danica Patrick]]

;Rugby
* The [[IRB Sevens World Series]], also in the union version of Sevens
* In [[rugby league]], the scrum-half/halfback
* [[Rugby Sevens]], a variant of [[rugby union]] and [[rugby league]] that contains only seven players per side instead of the standard 15 (union) or 13 (league)
* In [[rugby union]], the openside flanker
* The [[Rugby World Cup Sevens]], the World Cup for the union version of Sevens

;Track and field
* In [[cross country running]], a team traditionally consists of seven athletes

===Television===
====Networks and stations====
* The [[circle 7 logo]] used by numerous [[American Broadcasting Company|ABC]] network [[O&O]] stations in the U.S.
* Maximum number of VHF broadcast channels available in any TV market in the United States of America; they are channels 2, 4, 5, 7, 9, 11, and 13 in the [[New York-Newark SMSA|Greater New York City]] and [[Los Angeles-Long Beach SMSA]]s.
* [[ProSieben]] (''sieben'' being [[German language|German]] for seven), a television network in Germany
* [[Seven Network]], a television network in [[Australia]].

====Programs====
* [[7 Days (New Zealand)|''7 Days'']], a comedy gameshow based on news stories from New Zealand.
* The name of a television show ''[[7th Heaven]]''
* The name of a ''[[The Adventures of Super Mario Bros. 3]]'' cartoon, [[7 Continents for 7 Koopas]].
* ''[[Blake's Seven]]'' was a [[BBC television drama|BBC]] [[science fiction]] series that ran from 1978 to 1981
* ''[[Eureka Seven]]'', a science fiction and romance anime.
* Seven, an episodic character from the sitcom ''[[Married... with Children]]''.
* In the ''[[Seinfeld]]'' episode "[[The Seven]]", Seven is the name [[George Costanza]] desires to give his first-born, having allegedly promised this to the [[widow]] of baseball great [[Mickey Mantle]] (whose uniform number was 7). George is enraged, however, when his fiance's cousin and spouse copy the idea and give the name to their child.
* [[Seven Days (TV series)|''Seven Days'']], a science fiction show about the NSA using time travel.
* The name of one of the monsters in the cartoon television show ''[[Seven Little Monsters]]''
* In ''[[Star Trek: Voyager]]'', [[Seven of Nine]] (also called Seven for short) is one of the crewmembers
* The ''[[Ultra Series]]'' has two heroes with "Seven" in their name: Ultra Seven and [[Ultraman Neos|Ultra Seven-21]].
* ''[[Ultra Seven]]'', a television series aired in 1967, and the superhero of the same name. He is the honorary seventh member of the Ultra Garrison

===Video games===
[[File:Szmaragdy emeralds.png|thumb|left|150px|The 7 [[Sonic the Hedgehog (series)#Chaos Emeralds|Chaos Emeralds]] in [[Sonic R]]]]
* ''[[The 7th Guest]]'', produced by Trilobyte and released by Virgin Games in 1993[3], is an FMV-based puzzle horror video game.
* In the ''[[Ace Attorney]]'' series, 7 is a recurring number. For example: there is a 7 year age gap between the main character and his assistant, there is a 7-year gap between the plots of ''Ace Attorney 3'' and ''4'', Godot's favorite coffee blend is #107, the Chief of police, Gant's keycard number is 7777777.
* In ''[[Final Fantasy VII]]'' if anyone in your party's HP reaches to 7777, they will go berserk and strike the opponent a number of times at a damage rate of 7777. This is called the Lucky 7's. After the battle, however, the character's HP will be reduced to 1 to prevent this state from rolling over to another battle.
* 7 is a number used many times by [[Bungie Studios]] in their [[Halo series|''Halo'' series]] and [[Marathon trilogy|''Marathon'' trilogy]]. 7 appears in a variety of different contexts, from the stories of the games to the raw game coding also, the main character, master chief, also known as John 117; has a call sign of 117 and, 1x1x7=7 or 11x7=77.
* The 7 is a group of deadly mercenaries that kidnap the protagonist's family in the video game ''[[Kane & Lynch: Dead Men]]''.
* In the ''[[Killer7]]'' game, the number of individual personalities serving Harman Smith as part of the group of assassins called the [[Killer7]]
* In ''[[Kingdom Hearts]]'' there are seven Princesses of Heart (Snow White, Cinderella, Alice, Aurora, Belle, Jasmine, and Kairi (the only original character among them)). Seven (VII) is also the number of the character Saïx, a member of the antagonists Organisation XIII from [[Kingdom Hearts II]].
* Mario Brothers and Super Mario series:
** In ''[[Paper Mario: The Thousand-Year Door]]'', Mario's goal is to collect the seven Crystal Stars scattered across the world.
** In ''[[Super Mario RPG: Legend of the Seven Stars]]'', Mario and his gang need to collect seven stars to repair the Star Road.
** The number of [[Koopalings]] on ''[[Super Mario Bros. 3]]'' and ''[[Super Mario World]]''. It is also the number of worlds on ''Super Mario World'', not counting the Star World or the Special course; and it is also the number of worlds on ''[[Super Mario Bros. 2]]''.
* Nana (One of two Japanese readings for "seven" and also a common feminine name) is one of the supporting characters in ''[[Mega Man X: Command Mission]]''.
* In [[Sega]]'s ''[[Sonic the Hedgehog (series)|Sonic the Hedgehog]]'' video game franchise, there are often seven [[Sonic the Hedgehog (series)#Chaos Emeralds|Chaos Emeralds]]
* In ''[[Valkyria Chronicles]]'', you control Squad 7 of the militia force.
* In ''[[The World Ends with You]]'', one of the antagonists is a musician called "777."
* Zelda Series:
**In ''[[The Legend of Zelda: Ocarina of Time]]'', the main quest involves awakening the seven sages of seven elements to banish evil from the land of Hyrule. Further, the number of years separating the child and adult stages of the game is seven.
** Another Zelda title, ''[[The Legend of Zelda: A Link to the Past]]'', involves a similar quest in which the player must rescue seven maidens before confronting [[Ganon]].

==Places==
* The traditional count of [[Basque Country (historical territory)|Basque provinces]] as expressed in the slogan ''[[Zazpiak Bat]]''.
* The figurative number of [[seven seas|seas]]
* The [[Seven Virgins mountain range]] in [[Sri Lanka]], which was the scene of an [[air disaster]] on December 4, 1974, involving a DC-8 Series 55F passenger jetliner operated by the charter company [[Martinair]], which left 191 dead.

==Religion==
===Christianity===
[[File:Seven Days of Creation - 1765.jpg|thumb|200px|''Seven Days of Creation'' - 1765 book]]
The number seven (7) in the seven days of Creation is [[Typology (theology)|typological]] and the number seven appears commonly elsewhere in the Bible. These include:
* Seven days of Creation (Genesis 1) e.g., [[God]] rested on and sanctified the seventh day ([[Biblical Sabbath|Sabbath]])
* Anyone who dares to kill [[Cain]] 'will suffer vengeance seven times over' (Genesis 4:15)
* [[Lamech]] in his "Song of the Sword" claims that 'if Cain shall be avenged sevenfold', he himself shall be 'seventy-sevenfold' (Genesis 4:24)
* Seven years of plenty and seven years of famine in Pharaoh's dream (Genesis 41)
* In regards to the sin sacrifice, the [[kohen|anointed priest]] was to sprinkle the bullock's blood seven times before the lord (Exodus 4:6)
* Seven days of the feast of Passover (Exodus 13:3–10)
* Seven day week and the pattern concerning distribution and use of [[manna]] (Exodus 16)
* Seven year cycle around the years of Jubilee (Leviticus 25)
* Jericho's walls fall on the seventh day after seven priests with seven trumpets march around the city seven times (Joshua 6:8)
* Seven things that are detestable to the LORD (Proverbs 6:16–19)
* Seven Pillars of the House of Wisdom (Proverbs 9:1)
* Seven loaves [[Feeding the multitude|multiplied into seven basketfuls]] of surplus (Matthew 15:32–37)
* Peter asked [[Jesus]] if he should forgive those who sinned against him up to 7 times; Jesus responded by saying to forgive them 'seventy times seven times', remembering so the curse of Cain and the song of Lamech in Genesis 4.<ref><sup>21</sup>Then Peter came to Jesus and asked, 'Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?' <sup>22</sup>Jesus answered, 'I tell you, not seven times, but seventy times seven.'</ref>
* The [[sayings of Jesus on the cross|seven last words]] (or seven last sayings) of Jesus on the cross
* Seven men of honest report, full of the Holy Ghost and wisdom (Acts 6:3)
* In the [[Book of Revelation]], seven is a central figure of quantities: [[Seven Spirits of God]], [[Seven churches of Asia|Seven Churches]] (to which the book is addressed);
* Seven of the following appear in Revelation: golden lampstands(1:12), stars(1:16), torches of fire(4:5) seals(5:1), angels and their trumpets(8:2), last plagues(15:1), golden bowls(15:7), thunders(10:3), horns and eyes(5:6), diadems(12:3) and kings(17:10)

Other sevens in Christian knowledge and practice include:
* The [[Works of Mercy|Seven Corporal Acts of Mercy]] and [[Works of Mercy|Seven Spiritual Acts of Mercy]] of Roman Catholic, Anglican, and other traditions
* The [[Seven deadly sins]]: lust, gluttony, greed, sloth, wrath, envy, and pride
* [[Seven Gifts of the Holy Spirit]]
* The [[Seven Joys of the Virgin]] Mary, of Roman Catholic, Anglican, and other traditions
* The Seven [[Sacraments]] in the Catholic faith (though some traditions assign a different number)
* The [[Our Lady of Sorrows|Seven Sorrows of the Virgin]] Mary, of Roman Catholic, Anglican, and other traditions
* There are seven [[suicide]]s mentioned in the Bible ([[Old Testament|OT]] and [[New Testament|NT]]).<ref>[http://www.bible.org/illus.php?topic_id=1510 Bible.org: Sermon Illustrations<!--Bot generated title-->]</ref>
* The seven terraces of Mount [[Purgatory]] (one per deadly sin)
* The [[Seven Virtues]]: chastity, temperance, charity, diligence, kindness, patience, and humility
* In the [[genealogy]] in the [[Gospel of Luke]], Jesus is 77th in a direct line
* The number of heads of [[the three beasts]] (7 × 10 × 7 + 7 × 10 × 10 + 7 × 10 = 1260) of the [[Book of Revelation]], and of some other monsters, like the [[Lernaean Hydra|hydra]] and the [[Seven seals|number of seals]]

===Hinduism===
* The Sanskrit word ''sapta'' refers to number seven.
* Indian Music has "[[Saptak]] [[Swaras]]," seven octats (sa re ga ma pa dha ni) which are basics of music, using which hundreds of [[Rāga|Ragas]] are composed.
* Celestial group of seven stars are named as "[[Saptarshi|Sapta Rishi]]" based on the seven great saints.
* Seven Promises, Seven Rounds in Hindu Wedding and Seven Reincarnation
* According to Hinduism, there are seven worlds in the universe, seven seas in the world and seven Rishies (seven gurus) called sapta rishis.
* Seven hills at tirumala also known as ezhu malaiyan means Sevenhills god
* There are 7 [[Chakras]] in the basic model used in various eastern traditions and philosophies.

===Islam===
* The number of [[ayat]] in [[sura]]t [[al-Fatiha]]
* The number of layers of the Earth in [[Islam]]ic religion is seven
* The number of skies in [[Islam]]ic religion is seven
* The number of circumambulations ([[Tawaf]]) that are made around the [[Kaaba]]
* The number of walks between Al-Safa and Al-Marwah mountains—that is travelling back and forth—seven times during the ritual pilgrimages of Hajj and Umrah
* The number of [[heaven]]s in [[Islam]]ic religion, i.e. levels in heaven.
* The number of hells in hell is also seven i.e. levels in hell.
* The number of doors to hell is seven (for heaven the number of doors is eight).
* In Verse 12:46 (see [[Islamic view of Joseph]]) of the Quran, Joseph (Yusef) is asked to interpret the King's dream where seven fat cows were dreamt to have been devoured by seven skinny cows and seven green spikes, and others shrivelled.
* The number of the big sins or vices is seven which are from a [[Hadith]] of the prophet Mohamed : "Avoid the seven sins polytheism, witchcraft, the killing of the soul which Allah has forbidden except by right, consuming [[riba]], consuming the wealth of the orphan, to escape from the battles and slandering chaste women"

===Judaism===
[[File:Menora.svg|thumb|right|150px|The [[Menorah (Temple)|Menorah]] is a 7-branched [[Candelabra|candelabrum]]]]
* A highly symbolic number in the [[Torah]], alluding to the infusion of spirituality and Godliness into the [[Creation myth|creation]]. For example:
** [[God]] rested on and sanctified the seventh day ([[Shabbat]]). – [[Book of Genesis|Genesis]] 2:3. "Wisdom has built her house, she has hewn out her seven pillars." – Proverbs of [[Solomon]] son of [[David]] King of [[Israel]] 9:1
** A seven-day [[mikvah|purification]] period is required for one who has become ''tamei'' to become ''tahor''.
** The ''[[Shmita]]'' (Sabbatical) year arrives every seventh year.
** The [[Jubilee (Biblical)|Jubilee]] (''Yovel'') year comes after 7 times 7 years.
** The [[Counting of the Omer]] leading up to the Giving of the Torah is expressed as "7 times 7 weeks."
** There are 7 days of [[Passover]] and ''[[Sukkot]]'' when celebrated in [[Israel]].
** ''Shiv`a'' (another pronunciation of the Hebrew word for 7—({{Hebrew Name 1|שבעה||"seven"}})), is the number of days of mourning. Hence, one ''sits Shiva''. As in [[Shiva (Judaism)]]
* The weekly [[Torah]] portion is divided into seven ''[[Torah reading|aliyahs]]'', and seven Jewish men (or boys over the age of 13 who are considered men; Bar Mitzvah) are called up for the reading of these aliyahs during ''[[Shabbat]]'' morning services.
* Seven blessings are recited under the ''[[Jewish view of marriage|chuppah]]'' during a Jewish wedding ceremony.
* A Jewish bride and groom are feted with seven days of festive meals after their wedding, known as ''Sheva Berachot'' ("Seven Blessings").
* The number of ''[[Sukkot#Prayers|Ushpizzin]]'' (also known as the "Seven Shepherds") who visit the ''sukkah'' during the holiday of [[Sukkot]]: [[Abraham]], [[Isaac]], [[Jacob]], [[Joseph (Hebrew Bible)|Joseph]], [[Moses]], [[Aaron]], and [[David]].
* The number of nations God told the [[Israelite]]s they would displace when they entered the land of [[Israel]] (Deut. 7:1): the [[Biblical Hittites|Hittite]], the [[Girgashite]], the [[Amorite]], the [[Canaan]]ite, the [[Perizzite]], the [[Hivite]], and the [[Jebusite]].
* In [[Breslov (Hasidic dynasty)|Breslov]] tradition, the seven orifices of the face (2 eyes, 2 [[nostril]]s, 2 ears, and the mouth) are called "The Seven Candles."
* The [[Menorah (Temple)|Menorah]] (Hebrew: מנורה), is a seven-branched [[candelabrum]] lit by [[olive oil]] in the [[Tabernacle]] and the [[Temple in Jerusalem]]. The menorah is one of the oldest symbols of the [[Jew|Jewish people]]. It is said to symbolize the [[Burning bush]] as seen by [[Moses]] on [[Biblical Mount Sinai|Mount Sinai]] (Exodus 25).
* The number of times Cain will be avenged by God if he is murdered (Gen 4:15).
* The [[Israelites]] circled [[Jericho]] for 7 days and then the wall tumbled down.
* The 7 [[Sephirot]] of primary conscious emotion that are attributes of the creator.

===Others===

;Deity, being, or character
[[Image:Shichi fukujin.jpg|The [[Seven Lucky Gods]] in [[Japanese mythology]]|thumb|400px|left]]
* The [[Seven Lucky Gods]] refer to the seven gods of good [[luck|fortune]] in [[Japanese mythology]].
* The number of [[archangels]] according to some systems.
* In Buddhism, [[Buddha]] walked 7 steps at his birth.
* In [[Khasi people|Khasi]] mythology, the seven divine women who were left behind on earth and became the ancestresses of all humankind.
* The number of sleeping men in the Christian myth of the "[[Seven Sleepers]]."
* The number of sages in [[Hindu mythology]]; their wives are the goddesses referred to as the "Seven Mothers."
* In [[Iran]],<ref>[http://www.britannica.com/EBchecked/topic/1086220/number-symbolism/248164/7 ''Encyclopædia Britannica'' "Number Symbolism"]</ref> [[Spanish language|Spanish]], and other cultures that speak [[Romance Languages]], cats are said to have 7 lives as opposed to [[English language|English]], where cats are said to have 9 lives.
* In [[Irish mythology]], the epic hero [[Cúchulainn]] is associated with the number 7. He has 7 fingers on each hand, 7 toes on each foot, and 7 pupils in each eye. In the Irish epic [[Táin Bó Cúailnge]], Cúchulainn is 7 years old when he receives his first weapons and defeats the armies of the Ulaidh and his son [[Connla]] is 7 years old when he is slain by Cúchulainn in "The Death of Aife's Only Son."
* In [[Galicia (Spain)|Galician]] folklore, a seventh son will be a [[werewolf]]. In other folklores, after six daughters, the seventh child is to be a son and a werewolf. In other European folklores, the [[seventh son of a seventh son]] will be a child with special powers of healing and clairvoyant seeing, and in other cultures that [[seventh son of a seventh son]] would be a vampire.
* In [[Guaraní mythology]], the number of prominent [[Guaraní mythology#Seven legendary monsters|legendary monsters]].
* In the eponymous British folk tale, [[Thomas the Rhymer]] went to live in the faerie kingdom for 7 years.

;Place
* The number of main islands of mythological [[Atlantis]].
* The number of gateways traversed by [[Inanna]] during her descent into the [[underworld]].
* [[Quivira and Cíbola|Cibola]] was one of the legendary Seven Cities of Gold the Spanish thought existed.
* In the Bahá'í faith, the text ''[[Seven Valleys|The Seven Valleys]]'', by the Prophet-Founder [[Bahá'u'lláh]], relates the journey of the soul through the seven "valleys" of Search, Love, Knowledge, Unity, Contentment, Wonderment, and finally True Poverty and Absolute Nothingness.

;Scripture
* [[Circle Seven Koran]], the holy scripture of the Moorish Science Temple of America

;Thing, concept, or symbol
* The [[Seven-Branched Sword]] in Korean mythology.
* In [[Wicca]]n spirituality the number seven is said to hold a lot of divinity. It is known for being a very sound number and associates with many things.{{Citation needed|date=February 2011}}
* The[[Theosophy|Theosophical]] teachings of [[Alice A. Bailey]] divide the human race into seven [[psychological types]] called the [[Seven Rays#In Theosophy|Seven Rays]], which she calls "the basis of [[New Age]] [[psychology]]".
* The minor symbol number of [[yin and yang|yang]] from the Taoist [[yin-yang]].
* The number of palms in an [[Egypt]]ian ''[[cubit|Sacred Cubit]]''.
* The number of ranks in [[Mithraism]].
* The number seven is of particular significance within [[Cherokee]] cosmology.

;Time
* In British folklore, every 7 years the [[Queen of Elphame|Queen of the Fairies]] pays a tithe to [[Hell]] (or possibly [[Hel (location)|Hel]]) in the tale of [[Tam Lin]].

==Science==
===Astronomy===
* The number of daughters of [[Atlas (mythology)|Atlas]] in the [[Pleiades (star cluster)|Pleiades]] (also called the "[[Pleiades (Greek mythology)|Seven Sisters]]")
* The number of stellar objects in the [[solar system]] visible to the naked eye from Earth – the [[Sun]], the [[Moon]] and the five classical [[naked eye planets]]: [[Mars]], [[Mercury (planet)|Mercury]], [[Jupiter]], [[Venus]], and [[Saturn]].
* [[Messier object]] [[Ptolemy Cluster|M7]], a magnitude 3.5 [[open cluster]] in the constellation [[Scorpius]].
* The [[New General Catalogue]] [http://www.ngcic.org/ object] NGC 7, a 14th [[visual magnitude|magnitude]] spiral [[galaxy]] in the [[constellation]] [[Sculptor (constellation)|Sculptor]].
* The number of saints appearing in a constellation called "Saptharishi Mandalam" in Indian astronomy.
* The number of main stars in the constellations of the [[Big Dipper]] and [[Orion (constellation)|Orion]].
* The [[Saros cycle|Saros]] [http://sunearth.gsfc.nasa.gov/eclipse/SEsaros/SEsaros1-175.html number] of the [[solar eclipse]] series which began on [[-2590]] April 8 and ended on [[-1310]] May 16. The duration of Saros series 7 was 1,280.1 years, and it contained 72 solar eclipses.
* The Saros [http://sunearth.gsfc.nasa.gov/eclipse/LEsaros/LEsaros1-175.html number] of the [[lunar eclipse]] series which began on [[-2595]] July 15 and ended on [[-1008]] February 22. The duration of Saros series 7 was 1,586.6 years, and it contained 89 lunar eclipses.
* The Roman numeral VII stands for [[white dwarf]]s in the [[stellar classification|Yerkes spectral classification scheme]].
* The Roman numeral VII (usually) stands for the seventh-discovered satellite of a planet or minor planet (e.g., [[Jupiter VII]]).

===Biology===
* Almost all mammals have 7 [[cervical vertebrae]]
* Septuplets are seven offspring resulting from the same pregnancy.
* The number of spots on a [[Coccinella septempunctata|seven-spot ladybird]]
* There are 7 types of [[virus]] according to the [[Baltimore classification]]

===Chemistry===
[[File:Heptane3D.png|200px|thumb|right|[[Heptane]] is an [[alkane]] with 7 [[carbon]] [[atom]]s per [[molecule]]]]
* A [[heptamer]] is a compound made of seven sub-units
* A neutral [[pH]] value between [[acid]]ity and [[alkalinity]]
* The [[atomic number]] of [[nitrogen]]
* [[Heptane]] is an [[alkane]] with 7 carbon [[atom]]s in each [[molecule]]
* A [[period 7 element]] has 7 [[electron shell]]s
[[File:-TableImage.svg|500px|The [[periodic table]] has 7 [[Period (periodic table)|rows]] of known elements]]
* The number of periods, or horizontal rows of [[chemical element|elements]], in the [[periodic table]]

===Physics===
[[File:Rainbow-diagram-ROYGBIV.svg|thumb|right|200px|Isaac Newton's 7 colors of the rainbow]]
* There are 7 [[SI base unit]]s.<ref>{{cite web |url=http://www.bipm.org/en/si/si_brochure/chapter2/2-1/#2-1-2 |title=SI brochure, The seven SI base units |accessdate=2009-09-11}}</ref> These are a coherent set of units defined to measure 7 basic physical properties: [[metre]], [[kilogram]], [[second]], [[ampere]], [[kelvin]], [[mole (unit)|mole]], [[candela]]. The 7 SI base units are used to define all other SI units, which are known as [[SI derived unit]]s.<ref>{{cite web |url=http://www.bipm.org/en/si/si_brochure/chapter2/2-2/2-2-1.html |title=SI brochure, SI derived units |accessdate=2009-09-11}}</ref>
* [[Isaac Newton]] identified [[Roy G. Biv|7 colors]] of the [[rainbow]] – [[red]], [[orange (color)|orange]], [[yellow]], [[green]], [[blue]], [[indigo]], and [[violet (color)|violet]]

===Psychology===
* [[The Magical Number Seven, Plus or Minus Two]]

==Temporal, seasonal, and holidays==
* The seven [[days]] of the [[week]]
* The Kulin people of [[Australia]] living near the Dandenong Ranges traditionally have seven seasons. Some of the Native Americans of [[Montana]] also have seven seasons: [[chinookan|chinook]] season, muddy spring, green summer, gold summer (or dry summer), "Indian" Summer, late fall, and cold winter.
* The United States declared Independence in the 7th month of 1776.
* The [[Heptarchy]], from the ([[Greek language|Greek]] for ''seven realm'', is the name applied by historians to the period (500–850 CE) in [[History of England|English history]] after the [[Anglo-Saxons|Anglo-Saxon]] conquest of England, derived from the seven kingdoms of [[Northumbria]], [[Mercia]], [[East Anglia]], [[Kingdom of Essex|Essex]], [[Kingdom of Kent|Kent]], [[Kingdom of Sussex|Sussex]], and [[Wessex]], which eventually merged to become the [[Kingdom of England]] during the early 10th century.
* September was the seventh month in the ancient [[Roman calendar]], as its name indicates. After [[Julian calendar|the reform that led to the current order]], the seventh month is July.
* ''Septidi'' was the seventh day of the decade in the [[French Revolutionary Calendar]].
* The 7th glyph of the [[Maya Calendar]] is Blue Hand, it represents the days in creation and is associated with creative perfection. This is the glyph of the last day of their calendar that ends on December 21, 2012.

==Software and technology==
* 7 is the calling code of [[Russia]]. Only the North American Numbering Plan (+1) and Russia (+7) have a single-digit code.
* [[Windows 7]], the latest release of [[Windows]] series of operating systems from [[Microsoft]].
* Game developer [[Bungie]], famed for the ''[[Halo]]'' series of games, often references the number seven in their games.

==''Seven'' is also==
[[File:ICS Seven.svg|right|thumb|100px|[[International maritime signal flag]] for 7]]
* The number of basic principles of the [[bushido]]
* The number of [[chakras]]

==Notes==
{{Reflist}}

==See also==
{{Portal|Mathematics}}
* [[Septenary|Septenary (numeral system)]]
* [[Septenary (Theosophy)]]
* [[Seven climes]]
* [[Year Seven (School)]]

==References==
* Wells, D. ''[[The Penguin Dictionary of Curious and Interesting Numbers]]'' London: [[Penguin Group]] (1987): 70–71

==External links==
{{Commons category|7 (number)}}
{{Wiktionary|seven}}

{{DEFAULTSORT:7 (Number)}}
[[Category:Luck]]
[[Category:Integers|07]]
[[Category:Numerology]]
[[Category:Superstitions]]

[[ang:Seofon]]
[[ab:Быжьба]]
[[ar:7 (عدد)]]
[[arc:7 (ܡܢܝܢܐ)]]
[[ast:Siete]]
[[gn:Pokõi]]
[[av:Анкьго]]
[[az:7 (ədəd)]]
[[zh-min-nan:7]]
[[ba:Ете (һан)]]
[[be-x-old:7 (лік)]]
[[bi:Seven]]
[[bo:༧ (གྲངས་ཀ།)]]
[[ca:Nombre set]]
[[cv:7 (хисеп)]]
[[cs:7 (číslo)]]
[[ny:Sanu n'ziwiri]]
[[sn:Nomwe]]
[[tum:Vikhondi na tubili]]
[[da:7 (tal)]]
[[pdc:Siwwe]]
[[de:Sieben]]
[[myv:7 (ловома вал)]]
[[es:Siete]]
[[eo:Sep]]
[[eu:Zazpi]]
[[fa:۷ (عدد)]]
[[fo:7 (tal)]]
[[fr:7 (nombre)]]
[[ff:Joweeɗiɗi]]
[[ga:7 (uimhir)]]
[[gl:Sete]]
[[gan:7]]
[[hak:7]]
[[ko:7]]
[[ha:Bakwai]]
[[hr:Sedam]]
[[ig:Asaa]]
[[id:7 (angka)]]
[[ia:7 (numero)]]
[[ik:Tallimat malġuk]]
[[xh:Sixhenxe]]
[[it:7 (numero)]]
[[he:7 (מספר)]]
[[kn:ಏಳು]]
[[ka:შვიდი]]
[[rn:Indwi]]
[[kv:7 (сизим)]]
[[ht:7 (nonm)]]
[[ku:Heft]]
[[lbe:Арулва]]
[[la:Septem]]
[[lv:7 (skaitlis)]]
[[lb:Siwen]]
[[lt:7 (skaičius)]]
[[ln:Sambo]]
[[lg:Musanvu]]
[[lmo:Nümar 7]]
[[hu:7 (szám)]]
[[mk:7 (број)]]
[[ro:7 (cifră)]]
[[nah:Chicōme]]
[[fj:Vitu]]
[[nl:7 (getal)]]
[[cr:ᓃᐧᔖᔥᒡ]]
[[ja:7]]
[[nap:Sette]]
[[no:7 (tall)]]
[[nn:Talet 7]]
[[uz:7 (son)]]
[[pnb:7]]
[[koi:7 (сизим)]]
[[pl:7 (liczba)]]
[[pt:Sete]]
[[qu:Qanchis]]
[[ru:7 (число)]]
[[scn:Setti]]
[[simple:7 (number)]]
[[sl:7 (število)]]
[[srn:Numro 7]]
[[sr:7 (број)]]
[[sh:7 (broj)]]
[[fi:7 (luku)]]
[[sv:7 (tal)]]
[[tl:7 (bilang)]]
[[te:ఏడు]]
[[th:7]]
[[ti:ሸውዓተ]]
[[ve:Ṱhanu na mbili]]
[[tr:7 (sayı)]]
[[tk:7 (san)]]
[[bug:7 (nomoro)]]
[[uk:7 (число)]]
[[vi:7 (số)]]
[[vls:7 (getal)]]
[[war:7 (ihap)]]
[[wo:Juróom ñaar]]
[[ts:Nkombo]]
[[yi:7 (נומער)]]
[[zh-yue:7]]
[[zh:7]]

Revision as of 10:32, 1 June 2011

Pints owed to Hyslop by Pallett.