/ Dictionary / Index U unstoppable: Meaning and Definition of Find definitions for: un•stop•pa•ble Pronunciation: (un-stop'u-bul), [key] — adj. that cannot be stopped or surpassed; unbeatable: an unstoppable ball team. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: unstoppable (Thesaurus) unstop unstopper 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