Latin declension

Latin is an inflected language, and as such its nouns, pronouns, and adjectives must be declined (their endings alter to show grammatical case). A set of declined forms of the same word pattern is called a declension. There are five declensions, which are numbered and grouped by ending and grammatical gender. For simple declension paradigms, visit the Wiktionary appendices: , , , , . Each noun follows one of the five declensions, but some irregular nouns have exceptions.

Adjectives are of two kinds: those like bonus, bona, bonum "good" belong the 1st/2nd declension, using 1st declension endings for the feminine, and 2nd declension for masculine and neuter. Other adjectives such as celer, celeris, celere belong to the 3rd declension (there are no 4th or 5th declension adjectives).

Pronouns are also of two kinds, the personal pronouns such as ego "I" and tū "you (sg.)", which have their own irregular declension, and the 3rd person pronouns such as hic "this" and ille "that" which can generally be used either as pronouns or adjectivally. These latter decline in a similar way to the 1st/2nd noun declensions, but there are differences; for example the genitive singular ends in -īus or -ius instead of -ī or -ae.

The cardinal numbers ūnus "one", duo "two", and trēs "three" also have their declension (ūnus has genitive -īus like a pronoun), and there are also numeral adjectives such as bīnī "a pair" (or "two each"), which decline like ordinary adjectives.

A complete Latin noun declension consists of up to seven grammatical cases: nominative, vocative, accusative, genitive, dative, ablative and locative. However, the locative is limited to names of cities, small islands and a few other words.

They are often abbreviated to the first three letters.

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