noun adul·tery \ ə-ˈdəl-t(ə-)rē \
Updated on: 7 Mar 2018

Definition of adultery

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

Examples of adultery in a Sentence

  1. He found out that his wife had committed adultery.

  2. She accused her husband of adultery.

Recent Examples of adultery from the Web

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.

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.

Origin and Etymology of adultery

Middle English adultrye, adultery, alteration (conformed to Latin adulterium) of avoutrie, advoutrie, alteration (with addition of suffix -ie 2-y) 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 1adulterate

ADULTERY Defined for English Language Learners



Definition of adultery for English Language Learners

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

Law Dictionary


noun 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


play \ə-ˈdəl-tə-rər\ noun


play \-tə-rəs\ noun

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a ridiculous act or situation

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