/ Thesaurus / A Synonyms of atomic mass unit Find synonyms for: Noun1. atomic mass unit, mass unitusage: unit of mass for expressing masses of atoms or moleculesWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: loathe Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language