Definition and pronunciation
adulterous — adjective: relating to or involving sexual relations with someone other than one’s spouse; used in legal, journalistic, and religious contexts.
Pronunciation: /əˈdʌl.tər.əs/.
Easy explanation
Adulterous means a married person is having sex with someone who is not their spouse. People also use it for an affair that breaks an exclusive commitment.
Part of speech and grammar
- Adjective only: adulterous affair, adulterous relationship, adulterous conduct.
- Rare adverb: adulterously.
- Noun family: adultery (act), adulterer/adulteress (person—gendered; many prefer neutral “unfaithful spouse/partner”).
- Often appears before a noun (adulterous liaison), or after be (The relationship was adulterous).
Register and tone
Neutral-to-formal but can sound moralizing. Common in law, news, and policy. Everyday speech often uses cheat/cheating or affair.
Connection to sexuality
Direct. It describes consensual extramarital sex (or breach of exclusivity). It is not a term for non-consensual crimes—use specific legal labels for those.
Common collocations
adulterous affair; adulterous relationship; adulterous conduct; accused of adulterous behavior; adulterous liaison; adulterous spouse; adulterous couple; adulterous scandal; adulterous love; adulterous kiss (literary)
Idioms and fixed phrases
- caught in adultery (legal/religious phrasing; the adjective appears in narratives around this)
- fornicators and adulterers (stock pairing in older texts; the adjective appears as adulterous to modify affair/relationship)
Prepositions and nuance
- adulterous relationship with [someone] — names the third party.
- adulterous conduct with [someone] — legalistic phrasing.
- adulterous against [vows/spouse] — rare; better to use adultery against or simply adulterous conduct.
Meaning doesn’t change with prepositions; they just link the adjective to people or obligations.
Word comparisons
- adulterous vs faithful — opposites in marital commitment.
- adulterous vs extramarital — extramarital is descriptive/neutral; adulterous often carries moral or legal weight.
- adulterous vs cheating — cheating is everyday and may include nonsexual deceit.
- adulterous vs fornication — fornication traditionally means sex between unmarried people; adulterous involves at least one married person.
- adulterous vs open relationship — with explicit consent, sex outside marriage is not adulterous.
Real-life examples
- The petition cited an adulterous relationship as grounds for divorce.
- The ethics policy forbids undisclosed adulterous relationships between supervisors and direct reports.
- Reporters used alleged adulterous affair pending confirmation.
- In the novel, the adulterous couple wrestles with guilt and confession.
Sample sentences
- The court found no proof of adulterous conduct.
- Headlines focused on the politician’s adulterous affair rather than policy.
- She denied an adulterous relationship and requested privacy.
- The series treats the adulterous couple with nuance rather than condemnation.
- Legal guides distinguish adulterous behavior from criminal offenses involving lack of consent.
Synonyms
extramarital, unfaithful, cheating, faithless, disloyal, two-timing, illicit, immoral (value-laden), inconstant
Antonyms
faithful, loyal, monogamous, devoted, chaste, celibate
Related terms
adultery, adulterer, adulteress, affair, infidelity, betrayal, divorce, separation, reconciliation, paramour, co-respondent, prenuptial agreement, open relationship, consensual non-monogamy
Notes and etiquette
Be precise and non-inflammatory in professional writing. Use extramarital affair or unfaithful spouse when tone matters, and reserve adulterous for legal, policy, or carefully framed contexts. Do not use it to describe crimes; name those specifically.
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