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perfidious

[ per-fid-ee-uhs ]
/ pərˈfɪd i əs /
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See synonyms for: perfidious / perfidiously / perfidiousness on Thesaurus.com

adjective
deliberately faithless; treacherous; deceitful: a perfidious lover.
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Origin of perfidious

First recorded in 1530–40; from Latin perfidiōsus “faithless, dishonest”; cf. perfidy, -ous

OTHER WORDS FROM perfidious

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use perfidious in a sentence

British Dictionary definitions for perfidious

perfidious
/ (pəˈfɪdɪəs) /

adjective
guilty, treacherous, or faithless; deceitful

Derived forms of perfidious

perfidiously, adverbperfidiousness, noun
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
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