English → Latin
“perfidious” in Latin
perfidusthat breaks one's promise; false; faithless; dishonest; disloyal; deceitful; treacherous; unsafe; dangerousperfidiōsustreacherous, perfidiousīnfidēlisunfaithful; treacherous, disloyal; unbelieving, infidel
The English word perfidious itself goes back to Latin perfidus, through perfidiōsus.
Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864
perfidious
perfidus (as to single actions): perfidiosus (as to the whole character): perfidia praeditus (Cic., Flacc., 3); infldus; infidelis.
Quick answer
- What is the Latin word for perfidious?
- The usual Latin words for “perfidious” are perfidus, perfidiōsus, īnfidēlis. The right choice depends on the sense; see the distinctions below.
Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.