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Synonyms

adulterous

American  
[uh-duhl-ter-uhs] / əˈdʌl tər əs /

adjective

  1. characterized by or involved in adultery; illicit.

    an adulterous relationship.


adulterous British  
/ əˈdʌltərəs /

adjective

  1. of, characterized by, or inclined to adultery

  2. an obsolete word for adulterate

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does adulterous mean? Adulterous is used to describe a person who engages in or a relationship that constitutes adultery—a consensual sexual relationship or encounter between someone who’s married and a person they’re not married to (who may or may not be married to someone else). In other words, adultery can be between two people who are both married to other people, or between a married person and a nonmarried person. Typically, for something to be considered adulterous, at least one of the partners must be married. On the other hand, similar words like cheating, infidelity, and unfaithfulness can be used regardless of whether either person is married—they simply refer to a (usually sexual) relationship or encounter between people when one or both of them is in a committed relationship with someone else. When it happens with someone other than one’s spouse, a long-term relationship (often called an affair), a single sexual encounter, or anything in between can be considered adulterous. In some cases, a relationship may even be considered adulterous when it’s nonsexual but intimate (this is sometimes called an emotional affair). The words adultery and adulterous are especially used in a religious context, in which adultery is often considered a sin. The word adultery is also sometimes used in a legal context, such as during divorce proceedings. Adultery is associated with a considerable amount of stigma. The word adulterous is always used negatively and implies a critical judgment of such actions. Someone who participates in adultery can be called an adulterer. The word adulteress specifically refers to a woman who has engaged in adultery. (It has been more common throughout history for women to be called adulterous and to be blamed and punished for adulterous relationships than men.)Example: Just because it only happened once doesn’t mean it wasn’t adulterous.

Other Word Forms

  • adulterously adverb
  • unadulterous adjective
  • unadulterously adverb

Etymology

Origin of adulterous

First recorded in 1400–50; adulter(y) + -ous; replacing late Middle English avoutrious, advouterose

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Nearly a decade later, after a fight with her adulterous husband, the 25-year-old Follett left her apartment in Brookline, Mass., with $30 in her pocket and a notebook.

From Los Angeles Times • Oct. 29, 2025

I feel like the message of Jesus is clearly one of love—the adulterous woman in the Gospel of John, “You who are without sin cast the first stone.”

From Slate • Feb. 1, 2024

The ensemble cast features the Oscar-winning performances of Cloris Leachman as Ruth Popper, the adulterous wife of the high school sports coach and Ben Johnson as Sam the Lion, the town’s popular businessman.

From Washington Times • Nov. 23, 2023

Cook’s Tom Ripley-like story — and the wary narrator’s retelling of it — is loaded with fateful encounters, hidden agendas, shrouded identities, adulterous betrayals and brushes with death.

From Washington Post • Jan. 11, 2022

So this is what happened to the man who liberated the adulterous woman.

From "You Bring the Distant Near" by Mitali Perkins