Breadcrumb Home > Thesaurus > U Synonyms of unthinkable Find synonyms for: Adjective 1. unthinkable (vs. thinkable), impossible, inconceivable, out of the question, unimaginable, impossible, incredible#1, unbelievable usage: incapable of being conceived or considered WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of unthinkable (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: felicitous Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language