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
  • 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
  • Last month, six women interviewed by the Times described concerning behavior by Platner, including excessive drinking, infidelity, and, in one account, physical intimidation.
    — Allison Gordon, CNN Money, 6 July 2026
Definition of infidelity
Noun
  • Ultimately, the reassurances about community resources and air quality failed to quell the fury inside the room as residents took the microphone during the Q&A section and repeatedly expressed feelings of betrayal and mistrust.
    — Clara Harter, Los Angeles Times, 10 July 2026
  • Cupertino, which is slated to premiere in the fall on CBS, follows a former tech lawyer (Colter) who, after experiencing a betrayal from his former employer, teams up with another attorney to represent underdogs in litigation against tech giants.
    — Katie Kilkenny, HollywoodReporter, 10 July 2026
Definition of betrayal
Noun
  • Under the law, moral offenses — including adultery and same-sex relations — can carry penalties of up to 100 lashes.
    — Bonny Chu, FOXNews.com, 3 July 2026
  • Four other people were publicly caned on Thursday for online gambling and adultery.
    — ABC News, ABC News, 2 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
  • Heather Diehl | Getty Images More broadly, there can also be data-matching issues with Social Security numbers in ACA marketplace enrollment — meaning the lack of SSN may be a data issue, not misconduct, Oberlander said.
    — Greg Iacurci, CNBC, 3 July 2026
  • Allegations of employee misconduct are taken seriously and investigated thoroughly.
    — DeJanay Booth-Singleton, CBS News, 2 July 2026
Definition of misconduct
Noun
  • What constitutes treason is emerging as an early theme of House of the Dragon’s third season.
    — Amanda Whiting, Vulture, 29 June 2026
  • His attorney, Erias Lukwago, was taken from his house and later charged with an offense related to the concealment of treason.
    — Rodney Muhumuza, Los Angeles Times, 29 June 2026
Definition of treason
Noun
  • The professor was horrified by what appeared to be massive cheating in his course—cheating that was preventing most of the students from learning the material.
    — Nate Anderson, ArsTechnica, 8 July 2026
  • The central educational challenge of the coming decade is therefore not simply preventing cheating, but rebuilding cultures in which learning itself is once again perceived as inherently valuable, personally transformative, and socially essential.
    — Jason Benedict, Fortune, 7 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 11 Jul. 2026.

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Nglish: Translation of unfaithfulness for Spanish Speakers

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