Latin Nouns: Third Declension

Endings for Third Declension Nouns

Masculine/Feminine

Case Singular Plural
Nominative - -ēs
Genitive -is -um
Dative -ibus
Accusative -em -ēs
Vocative - -ēs
Ablative -e -ibus

Neuter

Case Singular Plural
Nominative - -a
Genitive -is -um
Dative -ibus
Accusative - -a
Vocative - -a
Ablative -e -ibus

Examples

mater, matris (f), mother
Case Singular Plural
nom. mater matrēs
gen. matris matrum
dat. matrī matribus
acc. matrem matrēs
voc. mater matrēs
abl. matre matribus
rex, regis (m), king
Case Singular Plural
nom. rex reges
gen. regis regum
dat. regī regibus
acc. regem regēs
voc. rex regēs
abl. rege regibus
corpus, corporis (n), body
Case Singular Plural
nom. corpus corpora
gen. corporis corporum
dat. corporī corporibus
acc. corpus corpora
voc. corpus corpora
abl. corpore corporibus

Additional Notes

What’s with the Hyphens?

Referring to the top two tables — since third declension nouns have a variety of different endings (-a, -e, -i, -o, -c, -l, -n, -r, -s, -t, -x, and -y in some cases), the paradigm charts above mark the nominative case with a hyphen. If the hyphen appears in other parts of the paradigm, it indicates that the nominative form should be used.

Cheat Sheet for Determining Gender

You can usually tell the gender of the noun by the following endings:

  • Masculine - Endings: -ō, -or, -ōs, -er, -es
  • Feminine - Endings: -ās, -ēs, -is, -ys, -x, -s (preceded by a consonant), -dō, -gō, -iō, -ūs
  • Neuter - Endings: -a, -i, -e, -y, -o, -l, -n, -t, -ar, -ur, -us

Neuter nouns

The accusative form of neuter nouns is always the same as its nominative form, no matter what declension.

Endings for Third Declension ĭ-stem Nouns

Masculine/Feminine

Case Singular Plural
Nominative - -ēs
Genitive -is -ium
Dative -ibus
Accusative -em -ēs
Vocative - -ēs
Ablative -e -ibus

Neuter

Case Singular Plural
Nominative - -ia
Genitive -is -ium
Dative -ibus
Accusative - -a
Vocative - -ia
Ablative -e -ibus

Examples

ignis, ignis (m), fire
Case Singular Plural
nom. ignis ignēs
gen. ignis ignium
dat. ignī ignibus
acc. ignem ignēs
voc. ignis ignēs
abl. igne ignibus
tussis, tussis (f), cough
Case Singular Plural
nom. tussis tusses
gen. tussis tussium
dat. tussī tussibus
acc. tussem tussēs
voc. tussis tussēs
abl. tusse tussibus
animal, animalis (n), animal
Case Singular Plural
nom. animal animalia
gen. animalis animalium
dat. animalī animalibus
acc. animal animala
voc. animal animalia
abl. animale animalibus

Additional Notes

What’s So Different about the ĭ-stem?

These are the main differences:

  • The genitive plural is -ium instead of -um.
  • The neuter plural forms of -a become -ia.

Is It an ĭ-stem?

An i-Stem third declension noun has one of the following characteristics:

  • The nominative and genitive forms are parisyllabic (meaning they have the same number of syllables). Examples: ignis (gen. ignis), hostis (gen. hostis).
  • Or the nominative inflection is monosyllabic (one syllable). The nominative inflection ends in -x or -s, and two consonants precede the suffix in the genitive form. Example: pars, partis (pars is only one syllable, it ends in -s, and the “rt” in partis (genitive form) qualifies it as having two consonants prior to the genitive suffix.
  • All nouns in the third declension ending in -e, -al, and -ar are neuter. Examples: mare (sea), portal (portal), templar (templar).

The Rare Accusative

In rare occasions, the accusative form of the masculine and feminine ĭ-Stem nouns is -im. If a word uses this inflection, the ablative for it is also changed to -i. Furthermore, its accusative plural form will most likely end in -is as well.

Recommended Latin Grammar Reading