Breadcrumb Home > Thesaurus > C Synonyms of crossopterygian Find synonyms for: Noun1. crossopterygian, lobefin, lobe-finned fish, bony fishusage: any fish of the order Crossopterygii; most known only in fossil formWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of crossopterygian (Dictionary) ✖ Related Content Daily Word Quiz: hortatory Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language