un·​faith·​ful | \ ˌən-ˈfāth-fəl How to pronounce unfaithful (audio) \

Definition of unfaithful

: not faithful:
a : not adhering to vows, allegiance, or duty : disloyal an unfaithful friend
b : not faithful to marriage vows suspected her husband of being unfaithful
c : inaccurate, untrustworthy an unfaithful copy of a document

Other Words from unfaithful

unfaithfully \ ˌən-​ˈfāth-​fə-​lē How to pronounce unfaithful (audio) \ adverb
unfaithfulness noun

Examples of unfaithful in a Sentence

colonists who later proved to be unfaithful to the cause of independence
Recent Examples on the Web While Cooper repeatedly denied being unfaithful, Kimball still believed the allegations were true. Kelly Wynne, PEOPLE.com, 5 Apr. 2022 Adrian Lyne's tale of adultery and murder is unfaithful to the ending of the original book. Clark Collis, EW.com, 19 Mar. 2022 Christy also revealed Danny had been unfaithful to her in the past. Kelly Wynne, PEOPLE.com, 24 Feb. 2022 Molly, Bloom’s unfaithful Penelope, is attracted to Stephen, who might even become her next lover. Jeffrey Meyers, WSJ, 21 Jan. 2022 Christy noted that Danny has been unfaithful before and worries that the same thing will happen again with Ileana. Emily Longeretta, Variety, 23 Feb. 2022 But Larry seemed fixated on the idea that Maya was unfaithful. CBS News, 19 Feb. 2022 Leopold Bloom, an adman, is avoiding his unfaithful wife and mourning a long-dead infant son. Anne Enright, The New York Review of Books, 5 Jan. 2022 Her husband would grieve his unfaithful wife and eventually remarry, and find a different species of happiness. The New Yorker, 13 Dec. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unfaithful.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of unfaithful

15th century, in the meaning defined above

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The first known use of unfaithful was in the 15th century

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Last Updated

12 Apr 2022

Cite this Entry

“Unfaithful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfaithful. Accessed 19 May. 2022.

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More Definitions for unfaithful


un·​faith·​ful | \ ˌən-ˈfāth-fəl How to pronounce unfaithful (audio) \

Kids Definition of unfaithful

: not faithful : disloyal

More from Merriam-Webster on unfaithful

Nglish: Translation of unfaithful for Spanish Speakers

Britannica English: Translation of unfaithful for Arabic Speakers


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