YOUR VOCABULARY, ONE WORD AT A TIME

perfidious

Adjective

IPA /pəˈfɪdiəs/

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Meaning in plain English

Deliberately disloyal and untrustworthy, especially by betraying someone.

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Pronunciation

perfidious/pəˈfɪdiəs/

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A friend is trusted with a secret
The secret is deliberately betrayed
Trust is broken

A perfidious friend is deliberately disloyal and betrays trust.

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In the adventure novel, a perfidious friend reveals the hero's hiding place.
The class debated whether the play's perfidious adviser ever showed genuine loyalty.

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In the adventure novel, a ________ friend reveals the hero's hiding place.

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perfidious — Deliberately disloyal and untrustworthy, especially by betraying someone.

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Deliberately disloyal and untrustworthy, especially by betraying someone.

Compare: In the adventure novel, a perfidious friend reveals the hero's hiding place.

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Word origin

From Latin perfidiosus, related to perfidia, meaning treachery.

Did you know?

Perfidious is stronger than unreliable: it suggests betrayal of trust.

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