Breadcrumb Home > Thesaurus > P Synonyms of perfidy Find synonyms for: Noun 1. perfidy, perfidiousness, treachery, disloyalty usage: betrayal of a trust 2. treachery, betrayal, treason, perfidy, dishonesty, knavery usage: an act of deliberate betrayal WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of perfidy (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 12 Steps to a New Year New Year's Resolution to Slim Down? Martin Luther King Speeches Books of the Bible: Old Testament Books in Order ✖ Related Content Daily Word Quiz: locution Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language