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

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 This sly, upbeat shuffle delves into a classic story song of infidelity. Jessica Nicholson, Billboard, 20 May 2022 Conversations With Friends is different from your typical tale of infidelity. Gabrielle Smith, Glamour, 16 May 2022 My sibling may dislike me but reserves white-hot hate for our father, who abandoned our mother some time ago, after a lifetime of infidelity. New York Times, 26 Apr. 2022 Orphée’s averted gaze as proof of infidelity — was a stirring and often shocking alchemy of despair and fury. Washington Post, 25 Apr. 2022 The case took unexpected twists and turns, like prosecutors revealing Michael Peterson’s bisexuality and infidelity, and even the couple’s former neighbor alleging an owl actually killed Kathleen, not her husband. Milan Polk, Men's Health, 5 May 2022 Their relationship develops slowly due to Dana’s tight-fisted control, influenced by her father’s infidelity. Michael Ordoña, Los Angeles Times, 23 Dec. 2021 In Act II, allusions to Sodom, Gomorrah and Noah’s ark are transplanted to the boardwalk of Atlantic City for George’s election as president of the Fraternal Order of Mammals and his foray into infidelity. Ayanna Prescod, Variety, 25 Apr. 2022 Amid his social media rampage, Rob also accused Chyna of drug abuse, alcohol abuse and infidelity. Dory Jackson,, 25 Apr. 2022 See More

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.

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

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Last Updated

23 May 2022

Cite this Entry

“Infidelity.” Dictionary, Merriam-Webster, Accessed 23 May. 2022.

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More from Merriam-Webster on infidelity

Nglish: Translation of infidelity for Spanish Speakers

Britannica English: Translation of infidelity for Arabic Speakers


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