/ Thesaurus / U Synonyms of unreplaceable Find synonyms for: Adjective1. irreplaceable (vs. replaceable), unreplaceable, unexpendableusage: impossible to replace; "irreplaceable antiques"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: inane Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language