Noun classifier

A classifier (abbreviated clf or cl), sometimes called a counter word, is a word or affix that is used to accompany nouns and can be considered to "classify" the noun depending on the type of its referent. Classifiers play an important role in the grammar of certain languages, especially East Asian languages, including Chinese and Japanese. In European languages classifiers are absent or marginal; an example of a word that may be considered to have the function of a classifier in English is head in phrases like "five head of cattle".

In languages that have classifiers, they are often used when the noun is being counted, that is, when it appears with a numeral. In such languages, a phrase such as "three people" is often required to be expressed as "three X (of) people", where X is a classifier appropriate to the noun for "people". Classifiers sometimes have other functions too; in Chinese they are commonly used when a noun is preceded by a demonstrative (word meaning "this" or "that"). Chinese classifiers are also commonly called measure words, although some writers make a distinction between the two terms.

Classifier handshapes appear in some sign languages; these may have a somewhat different grammatical function.

Certain parallels can be drawn between classifier systems and noun classes, although there are significant differences. Languages with classifiers may have up to several hundred different classifiers, whereas those with noun classes (or in particular, genders) tend to have a smaller number of classes, not always much dependent on the nouns' meaning, and with a variety of grammatical consequences.

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