Introduction#

Nouns in [[./index|Latin]] are words which refer to people, places, things and ideas. There are two types of nouns:
- Proper nouns are the names of particular people or places such as "Caesar" and "Rōma".
- All other nouns are known as common nouns.

Gender#

Every noun in Latin has a [[TODO|grammatical gender]] which can be either masculine, feminine or neuter. For the most part, each word needs to be learnt together with its gender, although there are certain rules which can sometimes make it possible to predict the gender of a given noun:
- The names of male people, rivers, winds, months and mountains are generally masculine - "pater", "Iūlius", "Tiberis", "auster", "Iānuārius", "Apennīnus".
- The names of female people, cities, countries, plants, trees, gems, many animals (especially birds) and most nouns which refer to abstract concepts are usually feminine - "māter" (mother), Iūlia (Julia), "Rōma" (Rome), "Ītalia" (Italy), "rosa" (rose), "pīnus" (pine), "sapphīrus" (sapphire), "anas" (duck), "vēritās" (truth).
- [[Nouns#Declension|Indeclinable]] nouns, infinitives, terms or phrases used as nouns, and quoted words are usually neuter - "fās" (right), "nihil" (nothing), "gummī" (gum), "scīre" (lit. "a knowing", knowledge), "valē" (a goodbye, a farewell).

Number#

Most [[Nouns#Introduction|Nouns]] can be in one of two numbers - singular or plural. Singular nouns are used to refer to only one instance of something, while plural nouns refer to multiple instances. Whether a noun is singular or plural is reflected by its [[Nouns#Declension|ending]].

Case#

Every [[Nouns#Introduction|noun]] can be in one of seven [[TODO|cases]] depending on its role in a given sentence. This is reflected by its [[Nouns#Declension|ending]].

Morphology#

Declension#

The vast majority of [[Nouns#Introduction|nouns]] change their form to reflect their [[Nouns#Case|case]] and [[Nouns#Number|number]], in a process known as declining. In dictionaries, [[Nouns#Introduction|nouns]] are listed by their [[TODO|nominative]] [[Nouns#Number|singular]] form followed by their [[TODO|genitive]] [[Nouns#Number|singular]] form and you must learn both forms for each noun.

[[Nouns#Introduction|Nouns]] are divided into five groups known as declensions depending on their [[TODO|genitive]] [[TODO|singular]] ending. Each ending stands for a combination of [[Nouns#Case|case]] and [[Nouns#Number|number]] and, for the most part, nouns belonging to the same declension use the same set of endings. To decline a noun, you just attach the appropriate ending to its stem. The stem is obtained by removing the ending from the noun's [[TODO|genitive]] [[Nouns#Number|singular]] form. For [[Nouns#Number|plūrālia tantum]] nouns, the [[TODO|genitive]] [[Nouns#Number|plural]] is used instead.

As you see, the stem can differ quite a lot from the nominative form.

Since there are seven [[TODO|cases]] and two [[Nouns#Number|numbers]], a single [[Nouns#Introduction|noun]] may have up to 14 forms. Moreover, there are five declensions for a total number of \(14 \times 5 = 70\) endings. Luckily, many endings are identical and there are some rules which can help you memorize them:
- The [[TODO|nominative]] and [[TODO|accusative]] of [[Nouns#Gender|neuter]] nouns are always the same and end in -a in the [[Nouns#Number|plural]]. This is one of the few rules with absolutely no exceptions.
- The [[TODO|dative]] and [[TODO|ablative]] [[Nouns#Number|plural]] of a given noun are always the same.
- The [[TODO|genitive]] [[Nouns#Number|plural]] always ends in -um.
- The [[TODO|vocative]] is always the same as the [[TODO|nominative]] except for [[Nouns#Declension|second declension]] [[Nouns#Number|singular]] nouns ending in -us.

First Declension#

These are the endings used by nouns belonging to the first [[Nouns#Declension|declension]].

The vast majority of [[Nouns#First Declension|first-declension]] nouns are [[Nouns#Gender|feminine]]. The only exceptions are nouns signifying male people such as "nauta" ("sailor") and "agricola" ("farmer") - these are [[Nouns#Gender|masculine]]. There are also some family and personal names, such as "Mūrēna", "Dolābella", "Scaevola" and "Hadria", which are also These are the endings used by nouns belonging to the first [[Nouns#Declension|declension]]. No [[Nouns#Gender|neuter]] nouns belong to the [[Nouns#First Declension|first declension]].

Second Declension#

There are two sets of endings used by nouns belonging to the second [[Nouns#Declension|declension]] depending on [[Nouns#Gender|gender]].

If the noun ends in -us, then its [[TODO|vocative]] [[Nouns#Number|singular]] ends in -e. The [[TODO|vocative]] and [[TODO|nominative]] forms of nouns ending in -er / -ir are identical . If a proper noun ends in -ius, then its [[TODO|vocative]] [[Nouns#Number|singular]] ends in -ī and not -iī (i.e. "Vergilius" becomes "Vergilī"), but the [[Orthography and Phonology#Stress Accent|stress]] remains on the same syllable as in the [[TODO|nominative]] [[Nouns#Number|singular]]. The same applies for the words "fīlius" ("son") and "genius" ("divine guardian").

Some nouns ending in -er do not have the -e in the stem, while others do.

Most nouns ending in -us, -er and -ir are [[Nouns#Gender|masculine]]. The major exceptions are the names of many countries and towns ending in -us ("Aegyptus", "Corinthus"), the names of many plants and gems ("alvus", "carbasus", "colus", "humus", "vannus") and many Greek nouns which retain their original gender ("arctus", "methodus") - all these are [[Nouns#Gender|feminine]]. There also the three nouns "pelagus" ("sea"), "vīrus" ("poison") and "vulgus" ("crowd") which are [[Nouns#Gender|neuter]]. Their [[Nouns#Case|nominative]] and [[Nouns#Case|accusative]] forms are identical, as with all neuters.

All nouns ending in -um are [[Nouns#Gender|neuter]].

Third Declension#

The third [[Nouns#Declension|declension]] is the most diverse and complicated of all the declensions.

Most nouns ending in -or, -ōs, -er, -es (gen. -itis), -ex (gen. -icis) are [[Nouns#Gender|masculine]]. Nouns ending in a [[TODO|consonant]] + -ō, -ās, -ēs, -is, -ūs, -x or -s are usually [[Nouns#Gender|feminine]]. Nouns ending in -a, -e, -l, -n, -ar, -ur or -us are predominantly [[Nouns#Gender|neuter]].

i-Stems#

There is a special subset of [[Nouns#Third Declension|third-declension]] nouns known as i-stems. These are a remnant of Old Latin and use slightly different endings. Moreover, there exist two types of i-stem nouns:
- pure i-stems - these use all of the i-stem endings;
- mixed i-stems - these use the i-stem endings only in the [[Nouns#Number|plural]].

If multiple forms are present, then the one outside parentheses is preferred.

Most [[Nouns#Gender|masculine]] and [[Nouns#Gender|feminine]] [[Nouns#Introduction|nouns]] which have the same number of [[TODO|syllables]] in the [[Nouns#Case|nominative]] and [[Nouns#Case|genitive]] [[Nouns#Number|singular]] are [[Nouns#i-Stems|pure i-stems]]. [[Nouns#Gender|Neuter]] [[Nouns#Introduction|nouns]] ending in -e, -al or -ar are also usually [[Nouns#i-Stems|pure i-stems]].

The following words are usually [[Nouns#i-Stems|mixed i-stems]]:
- [[Nouns#Introduction|Nouns]] ending in -ēs such as "mēlēs," "nūbēs", "vulpēs", etc.;
- [[Nouns#Introduction|Nouns]] whose [[Nouns#Case|nominative]] [[Nouns#Number|singular]] has only one [[TODO|syllable]] and ends in a [[TODO|consonant]] + -s or -x, such as "ars", "pōns", "arx", etc.;
- [[Nouns#Introduction|Nouns]] whose [[Nouns#Case|nominative]] [[Nouns#Number|singular]] has more than one [[TODO|syllable]] and ends in -ns or -rs, such as "cliēns" and "cohors";
- [[Nouns#Introduction|Nouns]] whose [[Nouns#Case|nominative]] [[Nouns#Number|singular]] ends in -tās and whose [[Nouns#Case|genitive]] [[Nouns#Number|singular]] ends in -tātis, such as "cīvitās";
- The words "Penātēs", "optimātēs" as well as nouns denoting birth whose [[Nouns#Case|nominative]] [[Nouns#Number|singular]] in -ās, -īs (with plural -ātēs, -ītēs), such as "Arpīnās" and "Quirīs";
- The words "dōs", "fraus", "glīs", "līs", "mās", "mūs", "nix", "nox", "strix", "vīs".

Fourth Declension#

These are the endings used by nouns belonging to the fourth [[Nouns#Declension|declension]].

The vast majority of [[Nouns#Fourth Declension|fourth-declension]] nouns are [[Nouns#Gender|masculine]]. However, some names of trees and plants as well as the words "acus", "anus", "colus", "domus", "manus", "nurus", "porticus", "socrus" and "tribus" are [[Nouns#Gender|feminine]]. The only [[Nouns#Gender|neuter]] nouns are "cornū", "genū", "pecū" and "verū".

Fifth Declension#

These are the endings used by nouns belonging to the fifth [[Nouns#Declension|declension]].

The [[Nouns#Case|locative]] is only encountered in the [[Nouns#Number|singular]] and even then only in very specific expressions. The -ēī ending of the [[Nouns#Case|genitive]] and [[Nouns#Case|dative]] [[Nouns#Number|singular]] for the words "fidēs", "spēs" and "rēs" is shortened to just -eī.

All [[Nouns#Fifth Declension|fifth-declension]] nouns are [[Nouns#Gender|feminine]] except for "diēs" ("day") and "merīdiēs" ("noon"), which are [[Nouns#Gender|masculine]].