/ Thesaurus / U Synonyms of unbelievably Find synonyms for: Adverb1. incredibly, improbably, implausibly, unbelievablyusage: not easy to believe; "behind you the coastal hills plunge to the incredibly blue sea backed by the Turkish mountains"2. unbelievablyusage: in an unbelievable manner; "he was unbelievably angry"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: heifer Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language