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

Lori already knew about the infidelity, but was only pushed to action once her daughter called her out on it. Ariana Romero,, "R29 Binge Club: Netflix’s Trinkets Recap," 15 June 2019 Tristan’s infidelity is the reason her family broke up. Jennifer Wright, Harper's BAZAAR, "Stop Blaming Women When Men Cheat," 11 Mar. 2019 Diana confronted Camilla about the affair in 1989, the couple officially separated in 1992, and Charles publicly admitted to his infidelity in a 1994 interview. Kayleigh Roberts, Marie Claire, "Prince Philip Reportedly Took Princess Diana's Side in Her Divorce from Prince Charles, According to These Private Letters," 9 Sep. 2018 In his fiction, Diaz often represents unhealthy romantic relationships tinged with abuse and infidelity. NBC News, "Pulitzer winner Junot Diaz accused of sexual misconduct by fellow writer," 5 May 2018 In his fiction, Diaz often represents unhealthy romantic relationships tinged with abuse and infidelity. Washington Post, "Author Junot Diaz faces sexual misconduct allegations," 4 May 2018 Defense attorneys cast Salman as a mother and a victim of Mateen's abuse and infidelity, as well as of the FBI's coercive investigators. Eric Levenson, CNN, "Jurors reach verdict in trial of Pulse gunman's widow," 30 Mar. 2018 Why not make a rom-com about Shirley MacLaine’s character, who was a Hollywood starlet in the 1960s, and Hector Elizondo, an architect and devoted husband who is heartbroken to learn of her long-ago infidelity? Chloe Angyal, Marie Claire, "The Only Thing Worse Than Valentine's Day Is Valentine's Day," 14 Feb. 2019 Gone are the infidelity pregnancy entrapment plotlines, traded in for ones about catfishing and the horrors of Internet dating. Julia Felsenthal, Vogue, "In Dirty John, Connie Britton Brings a Cautionary Tale to Life—And According to Her, the Timing’s Never Been Better to Talk About Con Men," 23 Nov. 2018

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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Dictionary Entries near infidelity







infield fly

Statistics for infidelity

Last Updated

18 Jun 2019

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Time Traveler for infidelity

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

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to take the place or position of

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