[adj] marked by deep ill will; deliberately harmful; "a malevolent lie"; "poisonous hate...in his eyes"- Ernest Hemingway; "venomous criticism"; "vicious gossip"
[adj] harsh or corrosive in tone; "an acerbic tone piercing otherwise flowery prose"; "a barrage of acid comments"; "her acrid remarks make her many enemies"; "bitter words"; "blistering criticism"; "caustic jokes about political assassination, talk-show hosts and medical ethics"; "a sulfurous denunciation"
[adj] extremely poisonous or injurious; producing venom; "venomous snakes"; "a virulent insect bite"
Synonyms
acerb, acerbic, acid, acrid, bitter, blistering, caustic, deadly, malevolent, malicious, poisonous, sulfurous, sulphurous, toxic, unpleasant, vicious, virulent, vitriolic