/ Thesaurus / C Synonyms of cotan Find synonyms for: Noun1. cotangent, cotan, trigonometric function, circular functionusage: ratio of the adjacent to the opposite side of a right-angled triangleWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: candid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language