/ Thesaurus / U Synonyms of unsufferable Find synonyms for: Adjective1. impossible, insufferable, unacceptable, unsufferable, intolerable (vs. tolerable), unbearable, unendurableusage: used of persons or their behavior; "impossible behavior"; "insufferable insolence"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: inutiae Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language