/ Thesaurus / U Synonyms of undeterminable Find synonyms for: Adjective1. indeterminable (vs. determinable), undeterminable, indeterminate, unascertainable, undiscoverable, unpredictable, incalculable, indeterminate#1, undeterminedusage: not capable of being definitely decided or ascertainedWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: philanthropy Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language