adjective false to one's obligations or allegiances; not loyal; faithless; treacherous.
Origin: 1470–80; <
Middle French desloial, Old French desleal, equivalent to
des- dis-1 +
leal loyal Related forms dis·loy·al·ist, noun
dis·loy·al·ly, adverb
Synonyms
unfaithful, perfidious, traitorous, treasonable.