adul·​tery | \ ə-ˈdəl-t(ə-)rē How to pronounce adultery (audio) \
plural adulteries

Definition of adultery

: voluntary sexual intercourse between a married person and someone other than that person's current spouse or partner also : an act of adultery

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What’s the difference between adultery and fornication?

In case you were wondering, the words adultery and adult are not etymologically related (in other words, adultery didn’t grow out of adult in the way that punditry grew out of pundit). Although both words come from Latin and share the same first five letters, adultery is from adulterāre (“to pollute, defile, commit adultery”), a word formed ultimately from the Latin elements ad- “to, near” and alter “other.” English adult comes from adultus, which is the past participle of the Latin word adolescere (“to grow up”).

In legal use there is a difference between adultery and fornication. Adultery is only used when at least one of the parties involved (either male or female) is married, whereas fornication may be used to describe two people who are unmarried (to each other or anyone else) engaging in consensual sexual intercourse.

Examples of adultery in a Sentence

He found out that his wife had committed adultery. She accused her husband of adultery.
Recent Examples on the Web But the Bible has many, many more verses about adultery. Jamie Ballard, Woman's Day, "This Is What the Bible Really Says About Sex, For Those Who Are Wondering," 4 Mar. 2020 His second wife, Anne Boleyn, mother of Elizabeth and the charismatic antagonist of the first two novels, has been beheaded for adultery. Parul Sehgal, New York Times, "Hilary Mantel’s Triumphant New Novel Brings Thomas Cromwell Across the Finish Line," 3 Mar. 2020 Full of crackling 80s dialogue and wry, self-deprecating humor, Ephron’s semi-autobiographical novel about adultery, divorce and therapy is skillfully narrated by the star of the 1986 screen adaptation, Meryl Streep. NBC News, "How to listen to audiobooks and where to get them: a beginner's guide," 10 Feb. 2020 Bryant had admitted committing adultery, but contended the act was consensual. Mark Medina, USA TODAY, "Kareem Abdul-Jabbar reflects on Kobe Bryant as a child, Lakers great, family man and storyteller," 20 Feb. 2020 Within hours, there would be allegations of adultery and a bloody fight. New York Times, "The federal trial of a former commander of the naval base put a spotlight on life at the isolated and secretive outpost best known for its terrorist court and prison.," 18 Jan. 2020 Within hours, there would be allegations of adultery and a bloody fight. Carol Rosenberg,, "Sex, power, and fury: the mystery of a death at Guantánamo Bay," 18 Jan. 2020 Upon the universal themes of love, rejection, adultery and Star-Is-Born fame, Joe DiPietro (book & lyrics) and David Bryan (music & lyrics) strike a tuneful, breezy tone that humanizes The Royals -- just not too deeply. Deborah Wilker, Billboard, "Princess Diana Musical 'Diana' Humanizes Royal Family: Review," 11 Apr. 2019 Even if the Family Resilience Bill meets the same fate as the adultery legislation, advocates said damage has already been done. NBC News, "Indonesia proposes bill to force LGBTQ people into 'rehabilitation'," 2 Mar. 2020

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

15th century, in the meaning defined above

History and Etymology for adultery

Middle English adultrye, adultery, alteration (conformed to Latin adulterium) of avoutrie, advoutrie, alteration (with addition of suffix -ie -y entry 2) of avoutre, borrowed from Anglo-French avulteire, avouteire, going back to Latin adulterium, from adulterāre "to defile by adultery, commit adultery with, pollute" + -ium deverbal noun suffix — more at adulterate entry 1

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Time Traveler for adultery

Time Traveler

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

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Statistics for adultery

Last Updated

28 May 2020

Cite this Entry

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

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More Definitions for adultery


How to pronounce adultery (audio)

English Language Learners Definition of adultery

: sex between a married person and someone who is not that person's wife or husband


adul·​tery | \ ə-ˈdəl-tə-rē \

Legal Definition of adultery

: voluntary sexual activity (as sexual intercourse) between a married man and someone other than his wife or between a married woman and someone other than her husband also : the crime of adultery — compare fornication

Other Words from adultery

adulterer \ ə-​ˈdəl-​tə-​rər How to pronounce adulterer (audio) \ noun
adulteress \ -​tə-​rəs How to pronounce adulteress (audio) \ noun

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Comments on adultery

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