Lexical category

The term lexical category is sometimes used for the major parts of speech noun, verb and adjective. It is not a perfect synonym of the terms part of speech/word class, because these terms also comprise minor categories (or functional categories) such as adpositions, subordinators, adverbs, etc., whereas lexical categories only comprise nouns, verbs and adjectives. Thus, lexical category is often contrasted with functional category, epecially in the generative tradition.

Synonyms

 * part of speech, word class, syntactic category (but these terms are somewhat wider)
 * major category (as opposed to minor category)

Reference
Baker, Mark. 2003. Lexical categories: nouns, verbs and adjectives. Cambridge: Cambridge University Press.

Link
Utrecht Lexicon of Linguistics

Other languages
German lexikalische Kategorie