[uhn-bi-lee-vuh-buh l]


too dubious or improbable to be believed: an unbelievable excuse.
so remarkable as to strain credulity; extraordinary: the unbelievable fury of the storm; an unbelievable athlete.

Origin of unbelievable

1540–50; un-1 + believable
Related formsun·be·liev·a·bly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for unbelievably

remarkably, extraordinarily, improbably, astonishingly

Examples from the Web for unbelievably

Contemporary Examples of unbelievably

Historical Examples of unbelievably

  • The Earth, unbelievably bright, was beckoning them once more.

    The Finding of Haldgren

    Charles Willard Diffin

  • If he had been strangely slow he was now unbelievably swift.

  • The ground was unbelievably rough and the jolting intolerable.

    Sand Doom

    William Fitzgerald Jenkins

  • His great arms were unbelievably powerful, but I could feel them dwindling.

    Beyond the Vanishing Point

    Raymond King Cummings

  • The Wabbly was unbelievably impersonal and horrible in its progress.


    Murray Leinster

British Dictionary definitions for unbelievably



in a manner that is hard to believe; astonishinglyit gets unbelievably hot
(sentence modifier) it is hard to believe that; incrediblyunbelievably, he remained utterly cheerful



unable to be believed; incredible or astonishing
Derived Formsunbelievability or unbelievableness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unbelievably



1540s, from un- (1) "not" + believable. Related: Unbelievably.

Online Etymology Dictionary, © 2010 Douglas Harper