/ Thesaurus / M Synonyms of mastoid bone Find synonyms for: Noun1. mastoid, mastoid process, mastoid bone, mastoidal, process, outgrowth, appendageusage: process of the temporal bone behind the ear at the base of the skullWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: abominable Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language