Ancient Greek nouns
In Ancient Greek, all nouns are classified according to grammatical gender (masculine, feminine, or neuter) and are used in a number (singular, dual, or plural). According to their function in a sentence, their form changes to one of the five cases (nominative, genitive, dative, accusative, or vocative). The set of forms that a noun will take for each case and number is determined by the declension that it follows.
The five cases of Ancient Greek each have different functions.
- ὁ Σωκράτης ἦν σοφός. "Socrates was wise."
The Ancient Greek genitive corresponds to the Proto-Indo-European genitive or ablative. When the genitive corresponds to the PIE genitive, it has meanings that can often be translated with the preposition "of" or the English possessive case:
- ὁ Ἀλέξανδρος εἰσῆλθε ἐις τὴν τοῦ Παρμενίωνος οἰκίαν. "Alexander entered the house of Parmenion." (or "Parmenion's house")
When the genitive corresponds to the Proto-Indo-European ablative case (this is the case when it is used with prepositions), it can often be translated by "from":
- τοῦ Ὁμήρου ἔμαθον τὴν τῶν ἐπῶν ποίησιν. "From Homer I learned the composition of epic poetry."
The Ancient Greek dative corresponds to the Proto-Indo-European dative, instrumental, or locative. When it corresponds to the dative, it expresses the person or thing that is indirectly affected by an action, and can often be translated with the prepositions "to" or "for":
- ὁ Ἰησοῦς εἶπε τῷ Παύλῳ: ἐλθὲ μετ' ἐμοῦ. "Jesus said to Paul: Come with me."
When the dative corresponds to the Proto-Indo-European instrumental, it expresses the thing with which something is done, and can often be translated by the preposition "with" or (rarely) the suffix "-wise":
- κόπτω πελέκει. "I am cutting with an axe."
When the dative corresponds to the Proto-Indo-European locative case (this is often the case when it is used with prepositions, it expresses location (sometimes figuratively) or time, and can often be translated by "in", "at", or "on"::
- ἑβδομηκοστῷ ἔτει ὁ Σωκράτης ἀπέθανε. "In his seventieth year Socrates died."
The accusative has meanings derived from the Proto-Indo-European accusative:
- ἔφαγε τὸ βρῶμα. "He ate the food."
When it is used with prepositions, it frequently indicates motion towards.
The vocative is used for addressing people or things. It is frequently the same as the nominative in the singular and always the same in the plural.
- ὦ Ἀλέξανδρε, Ἰᾶσον, ἔλθετε. "Alexander, Jason, come."
Accent of strong and weak cases 
For first- and second-declension nouns accented on the ultima and third-declension nouns with a single-syllable stem, the strong cases (nominative and accusative) have one type of accent, and the weak cases (genitive and dative) have another.
Specifically, the first- and second-declension nouns have acute in the strong cases, but circumflex in the weak cases —
- ἀγορά, ἀγοράν — ἀγορᾶς, ἀγορᾷ "gathering, marketplace"
- ἀγοραί, ἀγοράς — ἀγορῶν, ἀγοραῖς
- θεός, θεόν — θεοῦ, θεῷ "god"
- θεοί, θεούς — θεῶν, θεοῖς
— and the third-declension nouns accent the stem in the strong cases, but the ending in the weak cases:
- πούς, πόδα — ποδός, ποδί "foot"
- πόδες, πόδας — ποδῶν, ποσί
Both of these patterns are summarized by a single rule: post-stem accent in the strong cases, and pre-ending accent in the weak cases.
For first- and second-declension nouns, the rule is more complex. The thematic vowel (ο or ᾱ) counts as neither stem nor ending, but alternates between the two depending on which accent is considered. For post-stem accent, it counts as part of the ending; for pre-ending accent, it counts as part of the stem.
First declension 
The first declension or alpha declension is considered thematic, with long alpha (ᾱ) at the end of the stem, though it is derived from original athematic Indo-european forms. In Attic Greek, this changes to η everywhere except after ε, ι, or ρ. The first declension includes mostly feminine nouns, but also a few masculine nouns, including agent nouns in -της, patronyms in -ίδης, and demonyms.
The first-declension genitive plural always takes a circumflex on the last syllable. In Homeric Greek the ending was -άων (ᾱ) or -έων (from quantitative metathesis of *-ηων). -έων was contracted to -ῶν in Attic.
Feminine long a-stem 
Feminine short a-stem 
Some nouns have short ᾰ in the nominative, accusative, and vocative singular, but are otherwise identical to other feminine first-declension nouns. They are recessively accented.
These were formed with the suffix -ι̯ᾰ or ιᾰ. The ι̯ (written as y or i̯ in Proto-Indo-European, representing the semivowel [j]) undergoes one of several sound changes with the consonant at the end of the stem:
- *γλωχ-ι̯ᾰ → γλῶσσᾰ, Attic γλῶττᾰ "tongue" (palatalization; compare γλωχῑν "point")
- *μορ-ι̯ᾰ → μοῖρᾰ "portion" (metathesis; compare μόρος)
- *γεφυρ-ι̯ᾰ → γέφῡρᾰ "bridge" (compensatory lengthening of υ after loss of ι̯)
- *ἀληθεσ-ι̯ᾰ → ἀλήθειᾰ "truth" (assimilation of σ to ι̯; compare ἀληθές "something true")
Masculine a-stem 
|ποιητά (ᾰ)||same as
Second declension 
The second or omicron declension is thematic, with an -ο or -ε at the end of the stem. It includes one class of masculine and feminine nouns and one class of neuter nouns.
When a second-declension noun is accented on the ultima, the accent switches between acute for the nominative, accusative, and vocative, and circumflex for the genitive and dative. The only exceptions are Attic-declension and contracted nouns.
Masculine and feminine o-stems 
Masculine and feminine both end in -ος, and can only be distinguished by an article or adjective.
|masculine: ὁ||feminine: ἡ|
Neuter o-stems 
In the neuter, the nominative, accusative, and vocative are the same, with a singular in -ον and plural in -ᾰ. Other forms are identical to the masculine and feminine second declension.
Attic declension 
In Attic, some second-declension nouns and adjectives have endings with lengthened vowels. When a noun or adjective ends in -ηος or -ηον, quantitative metathesis (switching of vowel lengths) changes it to -εως or -εων.
- ο, ου, α → ω
- οι → ῳ
- original ῳ remains.
The placement of the accent does not change, even when the ultima is long, and all forms take an acute instead of a circumflex.
In these nouns, the vocative singular is the same as the nominative singular.
Contracted second declension 
In Attic, nouns and adjectives ending in -εος or -οος and -εον or -οον are contracted so that they end in -ους and -ουν.
When the ultima is accented, it takes a circumflex in all forms, including the nominative, accusative, and vocative.
Third declension 
The third declension group includes masculine, feminine and neuter nouns. It is an athematic declension that lacks the standard thematic vowels of the two thematic declensions above. This results in varied and often complex phonemic interactions between stem and suffix, especially so between adjacent consonants, that often make these nouns appear to be highly irregular compared to their straightforward thematic counterparts.
These nouns in the nominative singular end with the vowels α, ι, υ, ω or with the consonants ν, ρ, ς (ξ, ψ). They form the genitive case with -ος, ως or -ους.
Third-declension nouns may have one, two, or three stems. Each stem is used in different case-and-number forms. In nouns with two stems, the stem with the long vowel is called the strong stem, while the stem with the short vowel is called the weak stem. The strong stem is found at the nominative singular, and the weak stem in the genitive singular.
- ἡγεμών (long vowel, strong stem: nominative singular)
- ἡγεμόνος (short vowel, weak stem: genitive singular)
The α of the accusative singular and plural comes from ν pronounced as a vowel. It appears after consonants, or after a vowel where a consonant was lost (ϝ, ι̯, σ). The ending -νς always changes to -ας, except in the accusative plural of ἰχθύς, where it lengthens the preceding υ by compensatory lengthening.
These nouns end in -ν, -ρ, -ς (-ξ, -ψ). Based on the last letter of the stem, they are divided into two categories:
The mute-stem nouns have stems ending in -κ-, -γ-, -χ- (velar-stem nouns), -π-, -β-, -φ- (labial-stem nouns), -τ-, -δ-, -θ- (dental-stem nouns).
The semi mute-stem nouns have stems ending in -ν- (nasal-stem nouns), -λ-, -ρ- (liquid-stem nouns), -σ- (sibilant-stem nouns).
Nominative singular -ς and dative plural -σι cause pronunciation or spelling changes, depending on the consonant at the end of the stem.
at end of
|no consonant||—||-ς, -σι|
|dental||τ, δ, θ||-ς, -σι|
|velar||κ, γ, χ||-ξ, -ξι|
|labial||π, β, φ||-ψ, -ψι|
Velar- and labial-stems 
In the nominative singular and dative plural, the velars κ, γ, χ combined with σ are written as ξ, and the labials π, β, φ combined with σ are written as ψ.
Dental- and nasal-stems 
Stems in t 
In the nominative singular and dative plural, a dental τ, δ, θ before σ is lost: τάπης, not τάπητς.
If a noun is not accented on the last syllable and ends in -ις, -ης, or -υς, it often has an accusative singular in -ν and a vocative with no ending.
- ἡ χάρις, Πάρνης, κόρυς
- τὴν χάριν, Πάρνην, κόρυν (accusative)
- ὦ χάρι, Πάρνη, κόρυ (vocative)
Single-stems in nt 
In the nominative singular and dative plural, ντ before σ is lost, and the previous vowel is lengthened by compensatory lengthening. In the vocative singular, final -τ is lost, as Ancient Greek words cannot end in stops.
When a noun is accented on the last syllable, the vocative singular is identical to the nominative:
- ὁ ἰμάς
- ὦ ἰμάς (vocative)
Double-stems in nt 
These nouns have a weak stem in -οντ- and a strong stem in -ωντ-. The strong stem is used only in the nominative singular. The vocative singular is the weak stem without an ending. In both the nominative and vocative singular, the final τ disappears. In the dative plural, the σ in the ending causes the ντ to disappear, and the ο is lengthened to ου by compensatory lengthening.
Stems in at 
In these nouns, the stem originally ended in -ν̥τ- (with syllabic n), which changed to -ατ- in Greek. In the nominative singular, the final -τ disappeared.
Single-stems in an, en, in, on 
Some nouns have stems ending in -ν-. The nominative singular may end in -ς, causing compensatory lengthening, or have no ending.
Double-stems in en, on 
Some nouns have a strong stem in -ην-, -ων- and a weak stem in -εν-, -ον-. The nominative singular is the only form with the strong stem. Nouns of this class that are not accented on the last syllable use the weak stem without an ending for the vocative singular.
- ὁ γείτων
- ὦ γεῖτον (vocative)
Liquid-stems have stems ending in -λ- or -ρ-. Unlike mute-stems, these nouns do not change in spelling or pronunciation when the dative plural ending -σι is added.
Single-stems in er, or 
Some nouns end in -ηρ, -ωρ and take the endings without any sound changes.
Double-stems in er, or 
Some nouns have a nominative singular in -ηρ, -ωρ. The stem for the rest of the forms ends in -ερ-, -ορ-. Nouns in this class that are not accented on the last syllable use the weak stem without an ending for the vocative singular.
Triple-stems in er 
Some nouns have a strong stem in -ηρ in the nominative singular, a middle stem in -ερ- in other forms, and a weak stem in -ρ(α)- in yet other forms. The α in the dative plural was added for ease of pronunciation; the original form ended in -ρσι.
These include ὁ πατήρ "father", ἡ μήτηρ "mother", ἡ θυγάτηρ "daughter), ἡ γαστήρ "stomach", ἡ Δημήτηρ "Demeter", ὁ ἀνήρ "man".
The first three and γαστήρ use the weak stem in the genitive and dative singular and in the dative plural. The rest use the weak stem in the genitive, dative, and accusative singular and in the plural.
The vocative singular is usually the middle stem without an ending and accent on the first syllable. The exception is γαστήρ:
- ἡ γαστήρ
- ὦ γαστήρ (vocative)
Nouns in all three genders have stems ending in -εσ- or -οσ-. Before vowel endings, the σ is lost. In Attic, the ο or ε is contracted with the vowel of the ending. When σ combines with the -σι of the dative plural, the double σσ is simplified to single σ.
Masculines in es 
There are several masculine proper names with nominative singulars in -ης and stems in -εσ-. The vocative singular is the bare stem without an ending.
Feminines in os 
There are a few feminines with nominative singulars in -ως and stems in -οσ-.
Neuters in es 
Some neuter nouns have nominative, accusative, and vocative singulars in -ος, and stems in -εσ-.
These nouns end with ι, υ, ευ, αυ, ου, ω.
Stems in long o 
These take the suffixes without sound changes.
- nom.: ὁ ἥρως (hḗrōs - "hero"), gen.: τοῦ ἥρωος (hḗrōοs), voc.: ὦ ἥρως (hḗrōs) etc., nom.: οἱ ἥρωες (hḗrōes), gen.: τῶν ἡρώων (hērṓōn) etc.
Single-stems in u 
Because these nouns have a stem ending in -υ-, the accusative singular appears as -υν rather than -υα, and the accusative plural changes by compensatory lengthening from -υνς to -ῡς.
Triple-stems in i or u 
There are many feminine nouns in -ις, and a few masculine nouns in -υς, and one neuter noun: ἄστυ "town".
One stem is in -ι- or -υ-, another is in -ει- or -ευ-, and a third is in -ηι- or -ηυ-. But these stems underwent sound changes, so that they are no longer obvious. Before a vowel, the ι or υ in the second and third stem became the semivowel ι̯ or ϝ, and was lost. The long-vowel stem in the genitive singular was shortened, and the vowel in the ending lengthened (quantitative metathesis). Therefore, there appear to be two stems, ending in ι/υ and ε.
Stems in eu, au, ou 
The nouns in -ευς have two stems: one with short ε, another with long η. Both originally ended with digamma, which by the time of Classical Greek had either vanished or changed to υ. Thus the stems end in -ε(υ)-, from *-εϝ-, and -η-, from *-ηϝ-. In Attic Greek the η of the stem underwent quantitative metathesis with the vowel of the ending — the switching of their lengths. This is the origin of the -ως, -ᾱ, and ᾱς of the forms based on the stem in -η-.
The nouns with a vowel before the -εύς often contract the final ε of the stem (either original or from quantitative metathesis of η), which disappears into the following ω and ᾱ of the genitive and accusative singular and plural. As is the rule, the vowel resulting from contraction takes a circumflex:
- nom.: ἁλιεύς (halieús), gen.: ἁλιέως (haliéōs) and ἁλιῶς (haliôs), ἁλιέων (haliéōn) and ἁλιῶν (haliôn), acc.: ἁλιέα (haliéa) and ἁλιᾶ (haliâ), ἁλιέας (haliéas) and ἁλιᾶς (haliâs).
Stems in oi 
Stems in -οι- end in -ω in the nominative singular. The ι becomes the semivowel ι̯ and is lost, except in the vocative singular. There are no plural forms; when the plural does appear, it follows the second declension. The rest of the cases are formed by contraction.
Diminutive suffixes 
New nouns may be formed by suffix addition. Sometimes suffixes are added on top of each other:
- βύβλος búblos "papyrus"
- βιβλίον biblíon "book"
- βιβλάριον, βιβλιάριον, βιβλαρίδιον, βιβλιδάριον "small scroll"
- biblárion, biblarídion, biblarídion, biblidárion
- βιβλίδιον biblídion "petition"
Koine Greek 
None of these declensions change significantly in later Koine Greek grammar.
- The Inflectional Accent in Indo-European. Paul Kiparsky. Language. Vol. 49, No. 4 (Dec., 1973), pp. 794-849. Linguistic Society of America.
- Herbert Weir Smyth, Greek Grammar, par. 214 D: dialectal first-declension forms
- Smyth, par. 219: short-a first declension
- Smyth, par. 221: suffix -ι̯ᾰ in short-a first declension
- Smyth, par. 112: κι̯, χι̯ to ττ (σσ)
- Smyth, par. 111: "epenthesis" of ι̯ suffixed to an, on, ar, or
- Smyth, par. 37: compensatory lengthening
- Smyth, par. 225: genitive singular of masculine first declension
- βιβλάριον. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at Perseus Project