mis·treat \(ˈ)mi|strēt\transitive verb Etymology: Middle English mistreten, probably from Middle French mestreitier, mestraitier, from Old French, from mes- mis- (I) + treitier, traitier to treat — more at treat : to treat badly : abuse < administered a public thrashing to the landlord who had mistreated his brother — C.V.Woodward > • mis·treatment\“+\noun