"Perfidious" is a word in ENGLISH

perfidious ENGLISH
Definition:

Involving, or characterized by, perfidy.

perfidious ENGLISH
Definition:

Guilty of perfidy; violating good faith or vows; false
to trust or confidence reposed; teacherous; faithless; as, a perfidious
friend.

Few words of positivity

A child is born into a world of phenomena all equal in their power to enslave.

Peter Shaffer, Equus

WORD SUGGESTIONS
Laugh your heart out.

Did you hear about the burglar who fell in the cement mixer? Now he's a hardened criminal.

treacherous ENGLISH

Like a traitor; involving treachery; violating allegiance or faith pledged; traitorous to the state or sovereign; perfidious in private life; …

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