From French acide, from Latin acidus (“sour, acid”), from aceō (“I am sour”).
acid (comparative more acid, superlative most acid)
- Sour, sharp, or biting to the taste; tart; having the taste of vinegar.
- (figuratively) Sour-tempered.
- Of or pertaining to an acid; acidic.
- (music) Denoting a musical genre that is a distortion (as if hallucinogenic) of an existing genre, as in acid house, acid jazz, acid rock.
acid (countable and uncountable, plural acids)
- A sour substance.
- (chemistry) Any of several classes of compound having the following properties:
- Any of a class of water-soluble compounds, having sour taste, that turn blue litmus red, and react with some metals to liberate hydrogen, and with bases to form salts.
- Any compound that easily donates protons; a Brønsted acid
- Any compound that can accept a pair of electrons to form a covalent bond; a Lewis acid
- (slang) lysergic acid diethylamide (LSD)