part of speech

In grammar, a lexical category (also word class, lexical class, or in traditional grammar part of speech) is a linguistic category of words (or more precisely lexical items), which is generally defined by the syntactic or morphological behaviour of the lexical item in question. Common linguistic categories include noun and verb, among others. There are open word classes, which constantly acquire new members, and closed word classes, which acquire new members infrequently if at all.
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Noun
1. one of the traditional categories of words intended to reflect their functions in a grammatical context
(synonym) form class, word class
(hypernym) grammatical category, syntactic category
(hyponym) major form class