not loyal or faithful; faithless
Origin of disloyalOld French desloial: see dis- and loyal
Showing or characterized by a lack of loyalty; not loyal. See Synonyms at faithless.
Origin of disloyalLate Middle English from Old French desloial des- dis- loial loyal ; see loyal .
(comparative more disloyal, superlative most disloyal)
Middle English, from Anglo-Norman desleal, desloial