The second declension

The second declension

servus, puer, and bellum introduce three common second-declension shapes. The neuter rule is durable: nominative and accusative forms match, and their plurals end in -a.

Three nominative shapes share a genitive

Second-declension masculine nouns commonly end in -us, as in servus, or -er, as in puer. Neuters commonly end in -um, as in bellum and templum. Their dictionary entries reveal the shared genitive -ī: servus, servī m.; puer, puerī m.; bellum, bellī n. Some -er nouns retain e in the stem, while others such as ager, agrī lose it.

Masculine accusative singular is -um and plural is -ōs. Neuter nominative and accusative match: bellum in the singular, bella in the plural. This matching rule applies to neuter nouns in every declension, although the exact endings differ. The -a neuter plural should not be mistaken for a first-declension feminine singular.

Syntax decides whether a neuter form acts or receives

In bellum multōs virōs terret, bellum is neuter nominative singular and performs the action: ‘War frightens many men.’ In puer bellum timet, the identical form is accusative: ‘The boy fears war.’ Because neuter nominative and accusative look alike, the verb’s meaning and the other noun’s case identify the roles.

Now read puella magna templa videt. templa is neuter accusative plural, and magna agrees with it; puella is the singular subject. The translation is ‘The girl sees large temples.’ A singular verb does not conflict with the plural templa because an object does not govern agreement.

Masculine and neuter shapes

servus and puer are masculine second-declension nouns even though their nominatives look different. bellum is neuter. In every Latin neuter declension, nominative and accusative match; in the second declension their plural is -a. Therefore bellum can be subject or object, while bella can mean ‘wars’ as subject or object.