in·​fi·​del·​i·​ty | \ ˌin-fə-ˈde-lə-tē, -(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

Of course, the internet has a lot of feelings—some are shocked, some are happy, and some are accusing Offset of infidelity, though Cardi has not confirmed this herself. Rachel Epstein, Marie Claire, "Cardi B Explains Why She and Offset Broke Up," 5 Dec. 2018 The Jennifer Aniston, Brad Pitt, Angelina Jolie alleged love triangle was my first glimpse of infidelity. Samantha Leach, Glamour, "My Parents Divorced at the Same Time as Brad and Jen—and Yes, There Was an Angelina," 29 Nov. 2018 Bill Clinton had won the White House while being dogged by allegations of infidelity. Li Zhou, Vox, "The striking parallels between 1992’s “Year of the Woman” and 2018, explained by a historian," 2 Nov. 2018 But there were estrangements, and Jackson, a dandy who wore a pencil-thin mustache and huge diamond pinky ring, faced allegations by his wife of infidelity. Washington Post, "Joe Jackson, patriarch of musical Jackson family, dies at 89," 27 June 2018 Some of the details that have emerged about the last hours of the yacht are ugly, with whispers of drunkenness, rage, and accused infidelity. Nancy Bilyeau, Town & Country, "What Really Happened to Natalie Wood?," 29 Nov. 2018 In many ways, technology makes infidelity easier to pull off. Kim Komando, Fox News, "8 clever ways that tech can reveal a cheating spouse," 15 Sep. 2018 Toward the end of their ten year union, rumors of infidelity on both sides. Vogue, "Celebrity Divorces: 29 of the Most High-Profile Breakups," 27 July 2018 In the Godfather-esque visual, Jay-Z confesses his sins of infidelity to his wife inside of a church, in response to Beyoncé’s cheating accusations on Lemonade. Amanda Arnold, The Cut, "The Complete History of Beyoncé and Jay-Z’s Relationship in Music Videos," 17 June 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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Last Updated

15 Jan 2019

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

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