perfidious

[per-fid-ee-uhs] / pərˈfɪd i əs /

ADJECTIVE

treacherous

Synonyms

WEAK

betraying deceitful deceptive double-crossing double-dealing faithless false insidious misleading recreant shifty slick snake in the grass traitorous two-faced two-timing undependable unfaithful unloyal unreliable untrustworthy

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Samuel Pepys knew him; the British diarist thought him “a perfidious rogue.”

From The Wall Street Journal • Mar. 11, 2026

And not just for the big-ticket impulse buys, either — mostly for the tiny, perfidious ones.

From Salon • Jan. 11, 2026

The head of one of them, who preferred to remain anonymous, described it as a "perfidious and effective" strategy.

From Barron's • Nov. 1, 2025

But in the Disney+ series “Agatha All Along,” Hahn pulls from all the disparate strands of her body of work to play the perfidious, power-hungry witch Agatha Harkness.

From Los Angeles Times • Nov. 26, 2024

“Behold, campers, this vile and destructive creature! This killer of songbirds! This murderer of chipmunks! This perfidious predator!”

From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth

Vocabulary lists containing perfidious

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The Tempest

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