Noun-class system

In linguistics, a noun class is a particular category of nouns. A noun may belong to a given class because of the characteristic features of its referent, such as sex, animacy, shape, but counting a given noun among nouns of such or another class is often clearly conventional. Some authors use the term "grammatical gender" as a synonym of "noun class", but others use different definitions for each. Noun classes should not be confused with noun classifiers.

In general, there are three main ways by which natural languages categorize nouns into noun classes:

Usually, a combination of the three types of criteria is used, though one is more prevalent.

Noun classes form a system of grammatical agreement. The fact that a noun belongs to a given class may imply the presence of:

Modern English expresses noun classes through the third person singular personal pronouns he (male person), she (female person), and it (object, abstraction, or animal), and their other inflected forms. Countable and uncountable nouns are distinguished with many/much respectively. The choice between the relative pronoun who (persons) and which (non-persons) may also be considered a way of categorizing nouns into noun classes. A few nouns also exhibit vestigial noun classes, such as stewardess, where the suffix -ess added to steward denotes a female person. This type of noun affixation is not very frequent in English, but quite common in languages which have the true grammatical gender, including most of the Indo-European family, to which English belongs.

When noun class is expressed on other parts of speech, besides nouns and pronouns, the language is said to have grammatical gender.

In languages without inflectional noun classes, nouns may still be extensively categorized by independent particles called noun classifiers.

Common criteria that define noun classes include:

See Swahili for the semantic motivations for an elaborate noun-class system.

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