lexeme

n. basic unit of the lexicon of a language; vocabulary item

A lexeme is an abstract unit of morphological analysis in linguistics, that roughly corresponds to a set of words that are different forms of the same word. For example, in the English language, run, runs, ran and running are forms of the same lexeme, conventionally written as RUN. A related concept is the lemma (or citation form), which is a particular form of a lexeme that is chosen by convention to represent a canonical form of a lexeme. Lemmas are used in dictionaries as the headwords, and other forms of a lexeme are often listed later in the entry if they are unusual in some way.
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Noun
1. a minimal unit (as a word or stem) in the lexicon of a language; `go' and `went' and `gone' and `going' are all members of the English lexeme `go'
(hypernym) language unit, linguistic unit

<grammar> A minimal lexical unit of a language. Lexical analysis converts strings in a language into a list of lexemes. For a programming language these word-like pieces would include keywords, identifiers, literals and punctutation. The lexemes are then passed to the parser for syntactic analysis.
(1996-04-06)

Synonyms and related words:
antonym, articulation, expression, free form, glosseme, homograph, homonym, homophone, icon, lexical form, linguistic form, locution, logos, metonym, minimum free form, monosyllable, morpheme, phrase, polysyllable, semasiological unit, sememe, sign, signifiant, significant, syllable, symbol, synonym, term, token, type, usage, utterance, verbalism, verbum, vocable, word