perfidies

Noun

perfidy (countable and uncountable, plural perfidies)

1. A state or act of violating faith or allegiance; violation of a promise or vow, or of trust.

   Synonyms:

   betrayal, treachery, perfidiousness, breach of promise, breach of trust, double-dealing, Judas kiss, prodition, Punic faith, stab in the back

2. (international law) An illegitimate act of deception, such as using symbols like the Red Cross or white flag in a false claim of surrender to gain proximity to an enemy for purposes of attack.
   • Stratagems must be carefully distinguished strategy from perfidy, since the former are allowed, whereas the latter is prohibited.1921, Lassa Oppenheim with Ronald Francis Roxburgh, International law: a treatise, page 229
3. A state or act of deceit.
   • Germans could not get over the perfidy of it. It was unbelievable that the English, having degenerated to the stage where suffragettes heckled the Prime Minister and defied the police, were going to fight.1962, Barbara Wertheim Tuchman, The Guns of August, page 154

   Synonyms:

   perfidiousness, underhandedness, trickery, deceit, deceitfulness, deceptiveness, dissimulation, duplicity, fraudulence, fraudulency