(organic chemistry) A long-chain polyunsaturated fatty acid, having 20 carbon atoms and four double bonds, found in animal fats; it is essential for human nutrition, being a precursor to the production of prostaglandins.

(organic chemistry) A white crystalline organic acid, C₆H₅COOH; the simplest aromatic carboxylic acid; used as a food preservative and in many other industrial applications.

(pharmacology) The acetate ester of salicylic acid (aspirin)

(organic chemistry) A white crystalline organic acid, 2-hydroxybenzoic acid, C₆H₄(OH)(COOH), used in the production of aspirin and other industrial chemicals.

(organic chemistry) A white crystalline dicarboxylic acid, C₄H₈(COOH)₂; it has many industrial applications; when condensed with hexamethylene diamine it produces nylon.

(organic chemistry) A clear colourless organic acid, CH₃COOH, formed by the bacterial oxidation of ethanol through acetic fermentation; it is used as a solvent and has very many industrial applications; it is the major acidic component of vinegar.

(inorganic chemistry) A corrosive colourless liquid, HBrO₃; it is a powerful oxidizing agent, and is used in the manufacture of pharmaceuticals and some dyes; it reacts with bases to form bromates.

(organic chemistry) 2-methyl-propanoic acid, (CH₃)₂CHCOOH, an isomer of butyric acid, that occurs in carob beans and croton oil.

(organic chemistry) A very-long-chain saturated fatty acid, CH₃(CH₂)₂₄COOH, found in beeswax and carnauba wax.

(inorganic chemistry) A poisonous, white crystalline compound, H₃AsO₄, formed from arsenic pentoxide and water; it has the same structure as phosphoric acid, and is used in the manufacture of arsenates.