Definition of Acid

Noun: acid a-sid

Any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
Street name for lysergic acid diethylamide
- back breaker, battery-acid, dose, dot, Elvis, loony toons, Lucy in the sky with diamonds, pane, superman, window pane, Zen
A corrosive liquid with a pH less than 7; a solution of in water of a substance that releases hydrogen ions

Adjective: acid a-sid

Harsh or corrosive in tone
"a barrage of acid comments";
- acerb, acerbic, acrid, bitter, blistering, caustic, sulfurous [N. Amer], sulphurous [Brit, Cdn], virulent, vitriolic, acidulous, sulphureous [Brit]
Being sour to the taste
- acidic, acidulent, acidulous
(chemistry) having the characteristics of an acid
"an acid reaction"
(music, as a modifier) being a distortion (as if hallucinogenic) of an existing genre
"acid house"
(geology) rich in silica