Synonyms and related words :
acerb, acerbate, acerbic, acid, acidic, acidulent, acidulous, acrid, acrimonious, antagonistic, antipathetic, avenging, belligerent, bitter, burning, caustic, choleric, clashing, colliding, conflicting, despiteful, embittered, envenomed, evil, full of hate, grudgeful, hateful, hostile, implacable, irreconcilable, malevolent, malicious, malign, malignant, punitive, punitory, quarrelsome, rankled, repugnant, resentful, resenting, retaliatory, revanchist, revengeful, set against, sore, spiteful, splenetic, stewing, unappeasable, venenate, vengeful, venomous, vicious, vindicatory, vindictive, virulent, vitriolic, wicked