adjective.
Of, pertaining to, or representing perfidy; disloyal to what should command one's fidelity or allegiance.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adjective.
tending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans
Word Usage
"Then Miriam was furious, and complained to Minna about what she called her perfidious conduct; but Minna only laughed, and told her she could have Petrofsky instead. ""