PERFIDIOUS Synonyms: 65 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

Q: 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

Q: 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

Q: 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

perfidious

adjective

(ˌ)pər-ˈfi-dē-əs

Definition of perfidious next

as in traitorous

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

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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

Examples of perfidious in a Sentence

Recent Examples on the Web So much of what citizens know of our perfidious former president has come from her writing and reporting. —

Keith L. Runyon, The Courier-Journal, 17 Nov. 2022 But showing care for others, in the Republican party’s political trauma era, is a perfidious weakness. —

Rich Logis, The New Republic, 13 Oct. 2022 Marsha’s career was derailed by the Blacklist, a perfidious period of American history that has been endlessly chronicled and misunderstood. —

Alan K. Rode, Variety, 10 Sep. 2022 On the world stage, Ukraine consistently portrays Russia as a perfidious power that cannot be trusted to honor international agreements — and Moscow’s actions often make that characterization compelling. —

Laura King, Los Angeles Times, 24 July 2022 See all Example Sentences for perfidious

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'perfidious.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.