1. extremely poisonous or injurious; producing venom;
"venomous snakes""a virulent insect bite"
2. infectious; having the ability to cause disease
3. 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"