/ Thesaurus / I Synonyms of ibero mesornis Find synonyms for: Noun1. Ibero-mesornis, birdusage: sparrow-sized fossil bird of the Cretaceous period having a vestigial tail; found in Spain; considered possibly the third most primitive of all birdsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language