This adjective for a scathing comment or review literally refers to sulfuric acid
Subscribe to: Post Comments (Atom)... [DOC] [TLE] vitriolic - Dictionary Definition : Vocabulary.com [PAR] Mean, nasty, and caustic as the worst acid, vitriolic words can hurt feelings, ... 
Vitriolic is an adjective related to the noun vitriol  which means a metal 
sulphate.