/ Thesaurus / U Synonyms of unattainable Find synonyms for: Adjective1. unachievable, unattainable, undoable, unrealizable, impossible (vs. possible)usage: impossible to achieve; "an unattainable goal"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language