1
as in infidelity
lack of faithfulness especially to one's husband or wife
he eventually forgave his wife's unfaithfulness
Synonyms & Similar Words
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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
Synonyms & Similar Words
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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Example Sentences
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Recent Examples of unfaithfulness
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
Pete Hammond, Deadline, 27 Aug. 2025
Recent Examples of Synonyms for unfaithfulness
Noun
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Importantly, Miller says monkey barring is fundamentally different from polyamory — while the latter refers to loving multiple people at once and requires the consent of everyone involved, the former is arguably a form of infidelity.—
Nicole Fallert,
USA Today,
19 Sep. 2025
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And finances consistently rank among the top two causes of divorce—right alongside infidelity.—
Essence,
Essence,
19 Sep. 2025
Noun
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This final betrayal will be his undoing, as the enraged creature, doomed to live without connection, care, or love, finally snaps and destroys everything Victor holds dear.—
Thomas Page McBee,
Travel + Leisure,
16 Sep. 2025
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Your narrative, with its shifting of points of view among four longtime friends, allows for intimacy and drama as well as betrayals and loss as Desiree, Nakia, Monique and January (with Desiree’s estranged sister Danielle mostly on the sidelines) each tell their stories.—
Jane Ciabattari
September 16,
Literary Hub,
16 Sep. 2025
Noun
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Angela Paxton filed for divorce in July, accusing her husband of adultery.—
Lauren McGaughy,
ProPublica,
17 Sep. 2025
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In addition, Swazi law has a different definition of adultery for men and for women.—
The Editors,
JSTOR Daily,
15 Aug. 2025
Noun
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When does compromise become treachery or defeat?—
Literary Hub,
Literary Hub,
3 Sep. 2025
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Could Juno be behind this treachery, as payback for David destroying her spy corporation and for changing his oldest daughter into a killer?—
Demetrius Patterson,
HollywoodReporter,
27 Aug. 2025
Noun
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The allegations led to the October 2023 suspensions of Williams, Moore and Pryor after internal investigations into their handling of the county’s Dine-In 2 program found widespread financial misconduct first reported by The Sacramento Bee.—
Darrell Smith,
Sacbee.com,
18 Sep. 2025
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The suspension marks the third time in recent weeks that the archdiocese has publicly addressed allegations of misconduct involving leaders in its community.—
Judy L. Thomas,
Kansas City Star,
18 Sep. 2025
Noun
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Parliamentary officials met with at least 10 student unions, whose demands included the release of demonstrators and an investigation into Prabowo’s accusation about treason.—
Reuters,
NBC news,
4 Sep. 2025
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The main opposition party, CHADEMA, was disqualified in April and its leader Tundu Lissu remains in custody after he was charged with treason for demanding electoral reforms.—
Preeti Jha,
semafor.com,
29 Aug. 2025
Noun
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For the most part, lying and cheating do seem to be bad for you.—
Julie Beck,
The Atlantic,
17 Sep. 2025
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When yet another affair is discovered (Kate Upton), all three women team up to plot mutual revenge on their cheating, lying, three-timing SOB.—
Caitlin White,
Variety,
2 Sep. 2025
Cite this Entry
“Unfaithfulness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithfulness. Accessed 21 Sep. 2025.
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