A man who built his entire administration upon demanding unctuous loyalty from his allies now finds himself wounded by their shabby betrayal. You'd have to go back to one of Spain's humpbacked Hapsburgs to find court perfidy of the variety that is currently depleting the president's power. — Jack Hitt , Mother Jones ,

The petty Robespierres on the public stage appeal to "the real America" to rise up in fury against presidential perfidies ; yet in poll after poll the real America keeps telling Washington that it has gone bonkers. — David L. Kirp , Nation ,

I lived there off and on for twenty years, through graduate studies, marriage, the end of marriage, the perfidies of middle age, all the while unaware of passion. — Susan Barron , New England Monthly ,

They are guilty of perfidy.

he decided to forgive his wife's perfidy, choosing to ascribe it to a moment of uncharacteristic weakness