UNFAITHFUL Synonyms: 65 Similar and Opposite Words

unfaithful

adjective

ˌən-ˈfāth-fəl

Definition of unfaithful

as in traitorous

not true in one's allegiance to someone or something colonists who later proved to be unfaithful to the cause of independence

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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.

Recent Examples of unfaithful Nyong’o also plays Clytemnestra, the unfaithful wife of Agamemnon, whom Clytemnestra and her lover, Aegisthus, murder. — Encyclopedia Britannica, 1 July 2026 In Strangers on a Train, Rogers played Guy's unfaithful wife, whom Bruno offers to kill. — Emily Blackwood, PEOPLE, 29 June 2026 Platner is also an unfaithful spouse who mistreats women. — Chris Roemer, Baltimore Sun, 25 June 2026 Starring Yakusho Koji, the film follows a man released on parole after killing his unfaithful wife. — Naman Ramachandran, Variety, 13 May 2026 See All Example Sentences for unfaithful

Recent Examples of Synonyms for unfaithful

Adjective

Telemachus’ lone contribution is killing Melanthius, the traitorous Ithacan farmhand, thus preventing him from continuing to arm the suitors.

— Marlow Stern, Variety, 17 July 2026
And at the very center of Hell is Satan himself, the traitorous Archangel Lucifer, depicted as a monstrous creature with wings and three heads.

— Keith Cooper, Space.com, 11 May 2026

Definition of traitorous

Adjective

Even so, officials recommend residents consider backup ways to communicate in case cell service is unreliable.

— Sarah Horbacewicz, CBS News, 15 Oct. 2026
State officials say the federal data are unreliable and the demand comes too close to the election.

— Kevin Rector, Los Angeles Times, 15 Oct. 2026

Definition of unreliable

Adjective

Screening mammograms miss about one in eight breast cancers overall, and people with dense breasts are more likely to get false-negative results, the American Cancer Society reports.

— Samantha Agate, Kansas City Star, 14 Oct. 2026
Overall, screening mammograms miss about one in eight breast cancers, and people with dense breasts are more likely to get false-negative results.

— Samantha Agate, Charlotte Observer, 14 Oct. 2026

Definition of false

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unfaith

unfaithful

unfaithfulness

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“Unfaithful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithful. Accessed 16 Oct. 2026.

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Synonyms of unfaithful

adjective

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