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adjective per·fid·i·ous \(ˌ)pər-ˈfi-dē-əs\

: not able to be trusted : showing that someone cannot be trusted

Full Definition of PERFIDIOUS

:  of, relating to, or characterized by perfidy
per·fid·i·ous·ly adverb
per·fid·i·ous·ness noun

Examples of PERFIDIOUS

  1. We were betrayed by a perfidious ally.
  2. <a perfidious campaign worker revealed the senator's strategy to his leading rival for the nomination>

First Known Use of PERFIDIOUS


Synonym Discussion of PERFIDIOUS

faithless, false, disloyal, traitorous, treacherous, perfidious mean untrue to what should command one's fidelity or allegiance. faithless applies to any failure to keep a promise or pledge or any breach of allegiance or loyalty <faithless allies>. false stresses the fact of failing to be true in any manner ranging from fickleness to cold treachery <betrayed by false friends>. disloyal implies a lack of complete faithfulness to a friend, cause, leader, or country <disloyal to their country>. traitorous implies either actual treason or a serious betrayal of trust <traitorous acts punishable by death>. treacherous implies readiness to betray trust or confidence <a treacherous adviser>. perfidious adds to faithless the implication of an incapacity for fidelity or reliability <a perfidious double-crosser>.

Rhymes with PERFIDIOUS


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