- deliberately faithless; treacherous; deceitful: a perfidious lover.
Origin of perfidious
SynonymsSee more synonyms on Thesaurus.com
false, disloyal; unfaithful, traitorous.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for perfidious
The American Spectator proclaimed: “It is unlikely Republicans shall soon forget your perfidious betrayal.”Obama Escapes Scandals in New Jersey, but What’s in It for Christie?
May 29, 2013
Only then can they happily resume their perfidious business as usual.Perfidious Pakistani-American Games
Leslie H. Gelb
December 1, 2011
All is lost, for the sake of that inveigling, perfidious young Syren.The Politician Out-Witted
The czarina was strong-minded, but neither cruel nor perfidious.The Memoires of Casanova, Complete
Jacques Casanova de Seingalt
The sea is a perfidious element, but what is it to the blind malevolence of men?Romance
Joseph Conrad and F.M. Hueffer
An English poet has said of woman, 'Perfidious as the waves,' my son.A Romance of the West Indies
On one was a satire on the hypocritical rapacity of perfidious Albion.
- guilty, treacherous, or faithless; deceitful
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for perfidious
1590s, from Latin perfidiosus "treacherous," from perfidia (see perfidy). Related: Perfidiously; perfidiousness.
Online Etymology Dictionary, © 2010 Douglas Harper