/ Thesaurus / M Synonyms of mare's tail Find synonyms for: Noun1. mare's tail, cirrus, cirrus cloudusage: a long narrow flowing cirrus cloudWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language