WordNet sense 1 (harsh or corrosive in tone):

acerbic, acid, acrid, bitter, blistering, sulfurous, venomous, virulent, vitriolic, acerb, sulphurous

WordNet sense 2 (disagreeable to the senses, to the mind, or feelings ):

unpleasant

WordNet sense 3 (of a substance, especially a strong acid; capable of destroying or eating away by chemical action):

corrosive, erosive, mordant