/lek"sis/ , n. Ling.
the vocabulary of a language, as distinct from its grammar; the total stock of words and idiomatic combinations of them in a language; lexicon.
[ 1955-60; léxis speech, diction, word, text, equiv. to lég ( ein ) to speak, recount (akin to lógos account, word, L legere to read; see LOGOS, LECTION) + -sis -SIS ]