in·​fi·​del·​i·​ty | \ ˌin-fə-ˈde-lə-tē How to pronounce infidelity (audio) , -(ˌ)fī- \
plural infidelities

Definition of infidelity

1a : the act or fact of having a romantic or sexual relationship with someone other than one's husband, wife, or partner
b : unfaithfulness to a moral obligation : disloyalty
2 : lack of belief in a religion

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Examples of infidelity in a Sentence

She was convinced that her husband was guilty of infidelity. He has admitted to a number of marital infidelities.
Recent Examples on the Web At the time, the rapper’s alleged infidelity was said to have led to their breakup. Eric Todisco,, "Future Honored Six Women, Including Ex Ciara, He Has Children with Through Mother's Day Tweets," 12 May 2020 In 2010, Nilon's infidelity was exposed after Beauvais found a damning text from the other woman on his phone, which led the actress to send a scathing email to all of her husband's co-workers at the Creative Artists Agency. Ineye Komonibo,, "RHOBH Newbie Garcelle Beauvais Has Finally Moved On From Her Nasty Public Divorce," 6 May 2020 Despite the claims that infidelity played no part in the breakup, rumors are circling because of some weird timing: Cavallari cut ties with her former best friend Kelly Henderson earlier this year. Katherine J Igoe, Marie Claire, "Kristin Cavallari and Kelly Henderson: How Things Got So Messy Between Them," 29 Apr. 2020 Relationships seemed free of jealousy and infidelity because monogamy was the law of the land and hardly anyone strayed . . . Julian Gewirtz, Harper's Magazine, "To Rebel Is Justified," 30 Mar. 2020 Besides, 16% of respondents are bothered by social media infidelity. Niharika Sharma, Quartz India, "Nearly half of urban Indians are willing to forgive their partners for infidelity," 9 Dec. 2019 Unless the two of you had a previous understanding that infidelity was part of the deal, her actions would leave anyone feeling used., "Dear Annie: I’m still in love with my wife even though she lies to me and ignores me. What should I do?," 27 Aug. 2019 And even though the infidelity rumors arose during the Hometowns episode, she was given the opportunity to quickly squash them with a very sympathetic edit on the March 2 Women Tell All special. Kelsea Stahler,, "The Sun Has Set On Bachelor Villains & Brutal Producer Edits — Peter’s Season Is Proof," 12 Mar. 2020 But historians attribute the party-line vote, in no small part, to the weakness of the case; Clinton’s infidelity had no obvious effect on the affairs of state and his popularity surged as the impeachment process wore on., "In the end, only a handful of House Democrats voted to impeach Clinton and not a single Senate Democrat voted to remove him from office.," 28 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infidelity.' 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 infidelity

15th century, in the meaning defined at sense 2

History and Etymology for infidelity

Middle English infidelite, borrowed from Middle French infidelité, borrowed from Latin infidēlitāt-, infidēlitās "faithlessness, inconstancy," from infidēlis "unfaithful, disloyal" + -itāt-, -itās -ity — more at infidel entry 2

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Time Traveler for infidelity

Time Traveler

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

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Statistics for infidelity

Last Updated

3 Jun 2020

Cite this Entry

“Infidelity.” Dictionary, Merriam-Webster, Accessed 3 Jun. 2020.

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