D (disambiguation)

D is the fourth letter of the Latin alphabet.

D or d may also refer to:

Music

• D (musical note)
  • D major, a scale
  • D minor, a scale
  • D major chord; See Chord names and symbols
• Steinway D-274 or D, a concert grand piano manufactured by Steinway & Sons
• D Records, a former record label in Houston, Texas, US
• D, followed by a number can indicate a composition by Franz Schubert according to the Schubert Thematic Catalogue

Bands and musicians

• D (band), a Japanese rock/metal band
• "The D", one of the names of comedy rock band Tenacious D
• "d:" or "d:?", often used to refer to the Christian rock band Delirious?
• "D!" or "Dee!", names of Detlef Soost, a German dancer and choreographer
• D, the bass player for Australian band Testeagles

Albums

• D (Os Paralamas do Sucesso album), 1987
• D (White Denim album), 2011
• D (Deuter album), 1971
• Substance D, a drum and bass compilation album by Dieselboy

Entertainment and film

• D (film), a 2005 Bollywood film
• D Magazine, a magazine for the city of Dallas, Texas, US
• D, a weekly supplement to the Italian newspaper la Repubblica
• D (series), a video game series
  • D (video game), a game released in 1995 for the PC, 3DO, PlayStation and Sega Saturn
• Count D, a character in the anime/manga series Pet Shop of Horrors
• D is the character in a series of novels titled Vampire Hunter D by Hideyuki Kikuchi
• D is a nickname given to Count Dracula in the novel Dracula written by Bram Stoker
• D, one of the characters in Another Code: Two Memories (Trace Memory)
• Initial D, a 1995 Japanese manga and anime about mountain drifting that has spawned several arcade and console games
• Substance D, a fictional recreational drug in the novel and film A Scanner Darkly

Science

• D region, part of the ionosphere in earth science
• Deci- (d), the SI prefix meaning one tenth
• Day (d), in metrology

Mathematics

• d, the symbol for the total differential operator
• Thirteen (D in hexadecimal and other positional numeral systems with a radix of 14 or greater)
• Blackboard bold $\mathbb {D}$, representing the unit disk in the complex plane, or the decimal fractions; See Number
• d, often a variable for the diameter of a circle in geometry
• D and d, the derivative operators
• Five hundred, (D in Roman numerals)
• Divisor function (d(n)), the number of positive divisors of an integer n

Chemistry, biology and medicine

• Aspartic acid (D), in biochemistry
• Deuterium (D), an isotope of hydrogen
  • Deuteron (d), the nucleus of deuterium
• Vitamin D
• ATC code D Dermatologicals, a section of the Anatomical Therapeutic Chemical Classification System
• Haplogroup D (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup
• Haplogroup D-M174, a Y-chromosomal DNA (Y-DNA) haplogroup
• Diarrhea (D)

Physics

• Electric displacement field (D)
• d, thickness, diameter, relative density, lattice plane spacing, and degeneracy of vibrational mode, in molecular spectroscopy
• Debye (D), a unit of electrical dipole moment
• D, the name of mesons containing charm quarks in particle physics
• Diffusion coefficient (D), in molecular physics
• D band (disambiguation)

Solid state physics

• Debye–Waller factor (D)
• D as a function of energy, D(E), or wavenumber, D(k), a symbol for the density of states
• Diode (D), an electronic component

Astronomy

• D (for Degenerate), a white dwarf in stellar classification
• D/, for "destroyed/disappeared" in comet nomenclature
• D, a February 16 through 29 discovery in the provisional designation of a comet or asteroid

Technology and engineering

• Sensitivity index (d'), a statistic used in signal detection theory
• D battery, a standard size dry cell battery in electronics
• D, Mitsubishi Electric's mobile phones in Japan

Computing

• D - Minimal Protection, a security division in the Trusted Computer System Evaluation Criteria
• -d, a suffix of a daemon, a computer program that runs as a background process
• .d, a pathname component suffix for a directory; for example with the init program
• .d, a file format used for Agilent MassHunter mass spectrometry software

Programming languages

• D (programming language), a C++-like programming language developed by Walter Bright
• D (data language specification), the basis for the database query language Tutorial D and others
• D, a programming language designed to be used with the DTrace dynamic tracing framework

Places

• Deutschland (international license plate code for Germany)
• D River, in Oregon, US
• Detroit, US (nickname)

Business and economics

• Demand (D), in economics
• Federal Reserve Bank of Cleveland (serial numbers of United States dollars)
• Dominion Resources (New York Stock Exchange ticker symbol)
• Penny (British pre-decimal coin) (d)
• d, the common US measurement of the penny size (an approximation of length), of a nail

Transportation

• D (New York City Subway service), US
• D (Los Angeles Railway), a line operated by the Los Angeles Railway, US
• Drive, the forward cruising gears in an automatic transmission

Linguistics

• Voiced alveolar stop consonant ([d] or /d/), in the International Phonetic Alphabet
• Dingir (^D), the Sumerian sign for deity
• ’d, a contraction of the English words had and would

Other uses

• December, in calendars
• D (grade), a below average grade in education
• Defense (sports) (D)
• Died (d.)
• Daughter (d)
• D-Company, a criminal group
• Dominical letter D for a common year starting on Thursday
• Dominant person (D/), in dominance and submission
• Democrat, a member of the US Democratic Party
• D, a brassiere cup size
• d, the number of sides of dice in role-playing games
• 500 (number), D in Roman numerals

See also

• D- All Things Digital, an annual technology conference
• Denarius, a Roman coin
• Filetab-D, a port of the Filetab language based on decision tables
• D♯ (disambiguation)