adultery

noun

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

Did you know?

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The faith is rooted in the Vedas, an ancient Hindu scripture and prescribes the five lifetime vows: no alcohol, no addictions, no adultery, no meat and no impurity of body and mind. James Powel, USA TODAY, 9 Mar. 2025 Under Taliban rule, morality laws are strictly enforced, and activities considered immoral or against Islamic principles—such as pornography, adultery, or LGBTQ+ content—are harshly punished. Dan Perry, Newsweek, 28 Feb. 2025 Discrimination, lying, adultery, name -calling, belittling others, punching people and ignoring the poor, sick and elderly are now the accepted values of those who were concerned about the nation’s moral decline. Contributed Content, Twin Cities, 8 Feb. 2025 At the time of the case, Bryant admitted to adultery with a 19-year-old resort hotel worker in Colorado but denied the rape allegations, always maintaining that the encounter was consensual. George Ramsay, CNN, 8 Feb. 2025 See All Example Sentences for adultery

Word History

Etymology

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

First Known Use

15th century, in the meaning defined above

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

Browse Nearby Words

Cite this Entry

“Adultery.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/adultery. Accessed 16 Mar. 2025.

Kids Definition

adultery

noun
adul·​tery ə-ˈdəl-t(ə-)rē How to pronounce adultery (audio)
plural adulteries
: voluntary sexual intercourse between a married person and someone other than his or her spouse
adulterer
-tər-ər
noun
adulteress
-t(ə-)rəs
noun
adulterous
-t(ə-)rəs
adjective

Legal Definition

adultery

noun
adul·​tery
ə-ˈdəl-tə-rē
: 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
adulterer noun
adulteress noun

More from Merriam-Webster on adultery

Last Updated: - Updated example sentences
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