not adhering to allegiance, promises, vows, or duty: the faithless behavior of Benedict Arnold.
not trustworthy; unreliable.
without trust or belief.
being without religious faith.
(among Christians) bereft of Christian faith.

Origin of faithless

First recorded in 1250–1300, faithless is from the Middle English word faithles. See faith, -less
Related formsfaith·less·ly, adverb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for faithless

Historical Examples of faithless

  • That this or that good woman could do this or that faithless or mean thing, was nothing to her!

    Weighed and Wanting

    George MacDonald

  • Now they tell you, and seem to show you, that he is faithless.

    Fair Margaret

    H. Rider Haggard

  • Have I not, in the height of them, vowed revenge upon the faithless charmer?

    Clarissa, Volume 3 (of 9)

    Samuel Richardson

  • Where have you learned the disingenuous and faithless arts you employ?


    William Godwin

  • Not once since she began to get better, had Phemy alluded to her faithless lover.

    Heather and Snow

    George MacDonald

British Dictionary definitions for faithless



unreliable or treacherous
dishonest or disloyal
having no faith or trust
lacking faith, esp religious faith
Derived Formsfaithlessly, adverbfaithlessness, 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 faithless

c.1300, "unbelieving," from faith + -less. Meaning "insincere" is mid-14c. Related: Faithlessly; faithlessness.

Online Etymology Dictionary, © 2010 Douglas Harper