perfidy

PUR-fih-dee /ˈpɜːrfɪdi/
nounC2GRECAT
literaryarchaic

Deceitfulness; untrustworthiness; a breach of faith.

Perfidy is a high-literary term for a particularly cold-blooded or calculated betrayal.

The story behind the word. From the Latin 'perfidia', where 'per-' acts as a prefix meaning 'beyond' or 'away from', and 'fides' means 'faith'. To commit perfidy is to go 'beyond the bounds of faith'.

Word relationships

  • duplicity: Duplicity is being two-faced; perfidy is the actual act of breaking a solemn promise or faith.
  • fidelity: Fidelity is the quality of being faithful, which is the direct opposite of perfidy.

Commonly confused with

  • treachery: Treachery is the act; perfidy is the quality of being untrustworthy or the state of having broken faith.

Word family

  • perfidious (adjective): Deceitful and untrustworthy.

Collocations

  • act of perfidy
  • perfidious behavior
  • unparalleled perfidy

Example sentences

  • "He is at this time transporting large Armies of foreign Mercenaries to compleat the works of death, desolation and tyranny... with circumstances of Cruelty & perfidy scarcely paralleled in the most barbarous ages." The United States Declaration of Independence.

Memory hook

Perfidy: 'Per' (through) + 'Fidy' (faith). You poked a hole 'through' the 'faith' someone had in you. Faith broken into pieces.

When not to use

Too formal for casual conversation; use 'betrayal' or 'dishonesty' instead.

Fun facts

  • In international law, 'perfidy' is a specific war crime where a soldier feigns surrender or civilian status to kill an enemy.

Related words

treachery, duplicity

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