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
Synonyms & Similar Words
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Antonyms & Near Antonyms
1
as in infidelity
lack of faithfulness especially to one's husband or wife
he eventually forgave his wife's unfaithfulness
Synonyms & Similar Words
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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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of unfaithful
Sydney Bucksbaum, Entertainment Weekly, 14 Jan. 2026
Turns out, my husband has been suspicious of my evenings away and is now accusing me of being unfaithful.
—Harriette Cole, Mercury News, 29 Dec. 2025
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
See All Example Sentences for unfaithful
Adjective
Noth has not been formally charged or sued in connection with the allegations, and claimed that his only offense was being unfaithful to his wife, Tara Wilson.
—Sydney Bucksbaum, Entertainment Weekly, 14 Jan. 2026
Turns out, my husband has been suspicious of my evenings away and is now accusing me of being unfaithful.
—Harriette Cole, Mercury News, 29 Dec. 2025
Noun
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
See All Example Sentences for unfaithful
Recent Examples of Synonyms for unfaithful
Adjective
-
Russell fabricates a lie with the rest of the villains, and the heroes believe it, despite a warning from one traitorous tribemate.—
Literary Hub,
Literary Hub,
5 Dec. 2025
-
That video drew the ire of President Donald Trump, who deemed it traitorous.—
Mike Wall,
Space.com,
25 Nov. 2025
Noun
-
Burden’s family legacy was fractured by infidelity and a laissez faire attitude, at least in the public sphere, toward men behaving badly.—
Marc Weingarten,
Los Angeles Times,
31 Mar. 2026
-
During the documentary, the former couple also discussed Odom's infidelity.—
Ariana Quihuiz,
PEOPLE,
31 Mar. 2026
Noun
-
While some conservatives have described the war as a betrayal, many other Republicans have cheered on the president’s actions.—
Michelle L. Price,
Los Angeles Times,
1 Apr. 2026
-
The result is a second victimization — spiritual betrayal by those called to protect.—
Ed Gaskin,
Boston Herald,
29 Mar. 2026
Noun
-
The Bible teaches that lying, stealing, adultery and coveting your neighbor’s property are sins.—
Sun Sentinel Editorial Board,
Sun Sentinel,
16 Mar. 2026
-
The facile novelty of adultery is its own mask, a sexy way of dressing up a deep, frightened longing for security.—
Sara Holdren,
Vulture,
6 Mar. 2026
Adjective
-
Across much of Africa, where national electricity grids are often unreliable, mini-grids have emerged as a key alternative.—
ABC News,
ABC News,
1 Apr. 2026
-
Thus, the laser likely couldn’t perform properly, making the comparison to the oil unreliable.—
Leslie Baumann,
Miami Herald,
1 Apr. 2026
Noun
-
Undocumented immigrants venture from Mexico, often underestimating of the treachery of the landscape.—
Shi En Kim,
AZCentral.com,
26 Mar. 2026
-
Jonathan Cute kept probing the murky realms between tourism and treachery.—
Adam Ciralsky,
Vanity Fair,
19 Mar. 2026
Noun
-
The costs of decades of misconduct by Chicago police have grown enormous as the city settles lawsuit after lawsuit using expensive private counsel to handle most of the work.—
Chicago Tribune,
Chicago Tribune,
30 Mar. 2026
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And of course, Andrew being stripped of his titles and evicted from Royal Lodge, only to then be arrested for suspicion of misconduct in public office.—
Lizzie Lanuza,
StyleCaster,
30 Mar. 2026
Adjective
-
Five of the cases involved hospice care facilities in several cities across Los Angeles County that submitted false claims to Medicare for patients who were not terminally ill and were not eligible for services, prosecutors said.—
Thao Nguyen,
USA Today,
3 Apr. 2026
-
This means that precious time was likely lost at the beginning as police investigated a lead that was based on false assumptions.—
Lizzie Lanuza,
StyleCaster,
3 Apr. 2026
Cite this Entry
“Unfaithful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithful. Accessed 6 Apr. 2026.
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