1
as in infidelity
lack of faithfulness especially to one's husband or wife
his wife's perfidy was a moment of uncharacteristic weakness
Synonyms & Similar Words
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Antonyms & Near Antonyms
2
as in treachery
the act or fact of violating the trust or confidence of another
the full cost—both in compromised intelligence and in human life—of the double agent's perfidy is not yet known
Synonyms & Similar Words
Antonyms & Near Antonyms
Example Sentences
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Recent Examples of perfidy
All that said, Trump’s willingness to forgive the legal sins of former GOP congressman is a notable footnote to an often wretched history of pardon perfidy engaged in by presidents of both parties.
—
David Mark, The Washington Examiner, 31 Oct. 2025
Their perfidy is memorialized in the English language, though.
—Evan Osnos, New Yorker, 26 May 2025
The prior month, Vice President JD Vance had lodged his own complaints about Europe’s alleged perfidy, threatening that the United States might withdraw its security guarantees from Europe if the EU continued to aggressively regulate U.S. tech companies.
—Anu Bradford, Foreign Affairs, 21 Apr. 2025
Despite high trade deficits, the U.S. economy is strong
Trump and his advisers point to America’s lopsided trade numbers—year after year of huge deficits—as proof of foreigners’ perfidy.
—Time, 9 Apr. 2025
See All Example Sentences for perfidy
David Mark, The Washington Examiner, 31 Oct. 2025
Their perfidy is memorialized in the English language, though.
—Evan Osnos, New Yorker, 26 May 2025
The prior month, Vice President JD Vance had lodged his own complaints about Europe’s alleged perfidy, threatening that the United States might withdraw its security guarantees from Europe if the EU continued to aggressively regulate U.S. tech companies.
—Anu Bradford, Foreign Affairs, 21 Apr. 2025
Despite high trade deficits, the U.S. economy is strong
Trump and his advisers point to America’s lopsided trade numbers—year after year of huge deficits—as proof of foreigners’ perfidy.
—Time, 9 Apr. 2025
See All Example Sentences for perfidy
Recent Examples of Synonyms for perfidy
Noun
-
Kristy alleged infidelity as the reason for the pair’s split, per court records previously obtained by PEOPLE.—
Zoey Lyttle,
PEOPLE,
27 Jan. 2026
-
An attorney retained by Andrew’s family told ABC7 that moments before the killing, Andrew read a diary entry in which his wife described engaging in infidelity.—
Clara Harter,
Los Angeles Times,
24 Jan. 2026
Noun
-
With season 4 rapidly approaching, now's the time to prepare for the treachery to come.—
Randall Colburn,
Entertainment Weekly,
22 Dec. 2025
-
Instead of being killed, Ashur takes Spartacus’ life and is consequently rewarded for his treachery by the Roman Empire.—
Aramide Tinubu,
Variety,
1 Dec. 2025
Noun
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The book presents itself as a comic take on the classic adultery novel and a send-up of a narrow, self-conscious group of downwardly mobile New Yorkers.—
Literary Hub,
Literary Hub,
8 Jan. 2026
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The initial batch of documents showed that Angela Paxton sought the divorce on the grounds that Ken Paxton had committed adultery, but included no additional details.—
S.E. Jenkins,
CBS News,
19 Dec. 2025
Noun
-
Truist details allegations against former bank executives Truist’s complaint paints a picture of betrayal and covert meetings preceding the exodus.—
Charlotte Observer,
Charlotte Observer,
29 Jan. 2026
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Tears are shed, betrayal is discussed, and awful makeovers are brought back to light.—
Victoria Uwumarogie,
Essence,
29 Jan. 2026
Noun
-
Research on group dynamics shows that dissent is often interpreted as disloyalty rather than contribution.—
Benjamin Laker,
Forbes.com,
16 Jan. 2026
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The courts have warned against treating dissent as disloyalty.—
Chicago Tribune,
Chicago Tribune,
12 Jan. 2026
Noun
-
The president’s team moved quickly to prosecute the sheriff for treason.—
Michael Scherer,
The Atlantic,
22 Jan. 2026
-
Veteran opposition figure Kizza Besigye, a four-time presidential candidate, remains in prison after he was charged with treason last February.—
Los Angeles Times,
Los Angeles Times,
17 Jan. 2026
Cite this Entry
“Perfidy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/perfidy. Accessed 31 Jan. 2026.
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