perfidy
PUR-fih-dee
/ˈpɜːrfɪdi/
Deceitfulness; untrustworthiness; a deliberate breach of faith.
A highly formal and literary term implying a shocking, calculated, and malicious violation of a solemn oath.
The story behind the word. Perfidy comes from the Latin 'perfidia', which is formed from 'perfidus' (faithless). This is broken down into 'per-' (meaning through or to destruction) and 'fides' (faith). Literally, it means going 'through' faith to destroy it.
Word relationships
- treachery: Treachery is more common and can apply to physical hazards, while perfidy is strictly moral and highly formal.
- fidelity: Fidelity is strict observance of promises and duties, the exact opposite of perfidy.
Commonly confused with
- perjury: Perjury is specifically the crime of lying under oath in court, while perfidy is a general breach of faith.
Word family
- perfidious (adjective): Deceitful and untrustworthy.
Collocations
- act of perfidy
- unparalleled perfidy
- accused of perfidy
Idioms & expressions
- stab in the back
Example sentences
- "The empire's sudden invasion of its peaceful neighbor was condemned as an act of pure perfidy." A historical analysis of treaty violations.
Memory hook
Think of 'perfidy' as 'perfect infidelity'. It is the ultimate, most complete form of breaking trust. Perfect infidelity.
When not to use
Too dramatic for casual everyday betrayals, like a friend forgetting to call you back.
Fun facts
- In international law, 'perfidy' is a specific war crime where a combatant acts in bad faith by feigning surrender or civilian status to attack an opponent.
Related words
Explore more words
perfidious, treachery, perjure, perjury, treacherous, traduce
Also appears in
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