Synonyms & Antonyms of perfidious

not true in one's allegiance to someone or something
  • a perfidious campaign worker revealed the senator's strategy to his leading rival for the nomination

Synonyms for perfidious

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Frequently Asked Questions About perfidious

How is the word perfidious different from other adjectives like it?

Some common synonyms of perfidious are disloyal, faithless, false, traitorous, and treacherous. While all these words mean "untrue to what should command one's fidelity or allegiance," perfidious adds to faithless the implication of an incapacity for fidelity or reliability.

a perfidious double-crosser

When can disloyal be used instead of perfidious?

The words disloyal and perfidious are synonyms, but do differ in nuance. Specifically, disloyal implies a lack of complete faithfulness to a friend, cause, leader, or country.

disloyal to their country

Where would faithless be a reasonable alternative to perfidious?

The meanings of faithless and perfidious largely overlap; however, faithless applies to any failure to keep a promise or pledge or any breach of allegiance or loyalty.

faithless allies

When is false a more appropriate choice than perfidious?

The words false and perfidious can be used in similar contexts, but false stresses the fact of failing to be true in any manner ranging from fickleness to cold treachery.

betrayed by false friends

In what contexts can traitorous take the place of perfidious?

Although the words traitorous and perfidious have much in common, traitorous implies either actual treason or a serious betrayal of trust.

traitorous acts punishable by death

When could treacherous be used to replace perfidious?

While in some cases nearly identical to perfidious, treacherous implies readiness to betray trust or confidence.

a treacherous adviser

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The first known use of perfidious was in 1572

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Cite this Entry

“Perfidious.” Thesaurus, Merriam-Webster, Accessed 21 Sep. 2021.

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