/ Thesaurus / O Synonyms of os sesamoideum Find synonyms for: Noun1. sesamoid bone, sesamoid, os sesamoideum, bone, osusage: any of several small round bones formed in a tendon where it passes over a jointWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language