WordNet sense 1 (street name for lysergic acid diethylamide):

dose, dot, pane, superman, battery-acid, Elvis, Zen, back breaker, loony toons, Lucy in the sky with diamonds

WordNet sense 2 (being sour to the taste):

acidulous, acidulent

WordNet sense 3 (having a sharp biting taste):

sour

WordNet sense 4 (harsh or corrosive in tone):

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

WordNet sense 5 (disagreeable to the senses, to the mind, or feelings ):

unpleasant

WordNet sense 6 (being or containing an acid; of a solution having an excess of hydrogen atoms (having a pH of less than 7)):

acidic