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unfaithful

adjective
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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 Synonyms & Antonyms Example Sentences Learn More about unfaithful

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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 On the page left open, Green had written that White was unfaithful. — Marc Freeman, sun-sentinel.com, "Woman’s secret marriage to Romanian ended in murder. Killer’s lawyers push insanity defense.," 31 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, chicagotribune.com, "Ask Amy: Cheating boyfriend claims he was hacked," 17 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, Detroit Free Press, "Cheating boyfriend claims he was hacked," 17 Dec. 2020 During their passionate performance, acted out in old-timey dialogue and suggestive dance moves, Bowen plays a jealous woman who is convinced that Wiig, a man, has been unfaithful. — Mitchell Peters, Billboard, "Dua Lipa Plays a Nazi-Fighting Homewrecker in 'SNL' WWII Musical Sketch: Watch," 20 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, chicagotribune.com, "Ask Amy: Cheating boyfriend claims he was hacked," 17 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, Detroit Free Press, "Cheating boyfriend claims he was hacked," 17 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, oregonlive, "Ask Amy: She caught him cheating. He says he was hacked," 17 Dec. 2020 Some people who are unfaithful are able to own, apologize for, and rectify their mistake with their partners. — Amy Dickinson, chicagotribune.com, "Ask Amy: Cheating boyfriend claims he was hacked," 17 Dec. 2020

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.

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First Known Use of unfaithful

15th century, in the meaning defined above

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Time Traveler for unfaithful

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

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Last Updated

6 Jan 2021

Cite this Entry

“Unfaithful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfaithful. Accessed 17 Jan. 2021.

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More Definitions for unfaithful

unfaithful

adjective
How to pronounce unfaithful (audio)

English Language Learners Definition of unfaithful

: having a sexual relationship with someone who is not your wife, husband, or partner
: not accurate

See the full definition for unfaithful in the English Language Learners Dictionary

unfaithful

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

Kids Definition of unfaithful

: not faithful : disloyal

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More from Merriam-Webster on unfaithful

Thesaurus: All synonyms and antonyms for unfaithful

Nglish: Translation of unfaithful for Spanish Speakers

Britannica English: Translation of unfaithful for Arabic Speakers

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