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 show seemed uninterested in grappling with this messiness, and instead treated it just as age-inappropriate adultery. — Alan Sepinwall, Rolling Stone, 8 June 2022 Prosecutors have long enjoyed latitude to ignore outdated laws such as those penalizing adultery or let minor offenses such as recreational marijuana use slide. — Laura Kusisto, WSJ, 22 May 2022 Before the new process for separation came into effect, an individual had to accuse a spouse of desertion, adultery, or unreasonable behavior to be able to petition for a divorce. — Erika Page, The Christian Science Monitor, 16 May 2022 Adrian Lyne's tale of adultery and murder is unfaithful to the ending of the original book. — Clark Collis, EW.com, 19 Mar. 2022 The nuclear families behind that fence were as broken and troubled as yours and mine by divorce, perversion, addiction, deceit, disaffection, violence, adultery, and we can each complete our personal list. — David Mamet, National Review, 3 Mar. 2022 Each plot builds upon certain themes (often including family, addiction, adultery, forgiveness, and healing), but the storylines are clunky without actually being effective because they’re overburdened by drama. — Ineye Komonibo, refinery29.com, 1 Mar. 2022 The Taliban previously has imposed harsh penalties, including death sentences, for infractions linked to adultery, blasphemy, non-compliance with dress codes, working with the U.S. government and more. — Kiara Alfonseca, ABC News, 22 Aug. 2021 There was even a cottage industry of actresses willing to play the role of the other woman for couples who wanted a divorce on the grounds of adultery. — April White, Smithsonian Magazine, 24 May 2022 See More

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.

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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