unfaithfulness

noun

Definition of unfaithfulnessnext
1
as in infidelity
lack of faithfulness especially to one's husband or wife he eventually forgave his wife's unfaithfulness

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Antonyms & Near Antonyms
2
as in betrayal
the act or fact of violating the trust or confidence of another the jaw-dropping unfaithfulness of the person she had considered her best friend was deeply hurtful

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Antonyms & Near Antonyms
3
as in adultery
a sexual encounter or relationship between a married person and someone other than their spouse there were charges of unfaithfulness on both sides

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Antonyms & Near Antonyms

Example Sentences

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 unfaithfulness Coming to the glum realization that love isn’t outlasting infatuation is trickier to write about than a more incendiary subject like unfaithfulness, but Rodrigo pulls it off. — Chris Willman, Variety, 12 June 2026 According to The Daily Mail, unfaithfulness might have been the cause. — Lizzie Lanuza, StyleCaster, 12 Jan. 2026 Harbour also recently made headlines following the release of estranged wife Lily Allen's latest album, West End Girl, which contained references many interpreted as pointing toward alleged unfaithfulness on Harbour's part, though the actor isn't explicitly named in the lyrics. — Joey Nolfi, Entertainment Weekly, 7 Nov. 2025 Milvia Marigliano is a hoot as Coco Vulori, an old dear friend with some very loud opinions to express, and maybe the key to helping DeSantis solve his wife’s onetime unfaithfulness. — Pete Hammond, Deadline, 27 Aug. 2025
Recent Examples of Synonyms for unfaithfulness
  1. infidelity
  2. betrayal
  3. adultery
  4. treachery
  5. misconduct
  6. treason
  7. cheating
Noun
  • The same day Diana wore the gown, her estranged husband admitted to infidelity on national television.
    — Bailey Bujnosek, InStyle, 9 July 2026
  • Plots tend to involve women in various types of distress, facing things like murder, stalking, infidelity, illicit love, kidnapping, and storm-chasing serial killers.
    — Brianna Zigler, Entertainment Weekly, 7 July 2026
Definition of infidelity
Noun
  • But the speech gave him a fresh outrage through which to revisit an old defeat, accuse his own government of betrayal and force the press to spend the evening adjudicating his claims.
    — Aidan McLaughlin, Vanity Fair, 17 July 2026
  • That then tied into the idea of the betrayal and manipulation of xenia and how that fed into the collapse of this civilization.
    — Bilge Ebiri, Vulture, 17 July 2026
Definition of betrayal
Noun
  • In the graphic sequence, Lannister is forced to walk naked through the streets as punishment for committing adultery.
    — Edward Segarra, USA Today, 17 July 2026
  • Hundreds of pages of filings in a civil lawsuit and countersuit detail allegations of fraud and elder abuse, years of adultery, and a battle for property, luxury sports cars and cash.
    — Amber Gaudet, Charlotte Observer, 10 July 2026
Definition of adultery
Noun
  • Guides spoke of the monthlong siege that ended only because of the treachery of a local noble who turned on the sultan and allowed British troops to scale the walls.
    — Ishaan Tharoor, New Yorker, 2 July 2026
  • This is not treachery but the truest and noblest affection.
    — Ann Manov, Harpers Magazine, 23 June 2026
Definition of treachery
Noun
  • And when misconduct does happen — rarely — security protocols frequently catch it.
    — Ali Swenson, Chicago Tribune, 18 July 2026
  • Hanaway’s office filed a petition to remove Johnston from office, alleging misconduct, according to a news release from the attorney general’s office.
    — Caroline Zimmerman, Kansas City Star, 17 July 2026
Definition of misconduct
Noun
  • Alfred Dreyfus, whose wrongful 19th century treason conviction exposed deeply rooted anti-Jewish bias in France.
    — Masha Macpherson, Los Angeles Times, 12 July 2026
  • What constitutes treason is emerging as an early theme of House of the Dragon’s third season.
    — Amanda Whiting, Vulture, 29 June 2026
Definition of treason
Noun
  • Despite multiple requests from test takers and lawmakers, the DMV has not provided any details about the nature of the alleged cheating, and some of those who must take the test over feel like they’ve been unfairly accused.
    — Clara Harter, Los Angeles Times, 16 July 2026
  • But that successful act of cheating is central to Maradona’s legend, as is his defiance in the aftermath.
    — Ishaan Tharoor, New Yorker, 16 July 2026
Definition of cheating

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Cite this Entry

“Unfaithfulness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithfulness. Accessed 22 Jul. 2026.

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Nglish: Translation of unfaithfulness for Spanish Speakers

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