庚酸，结构式CH₃(CH₂)₅COOH。

无色具腐败脂肪气味的透明油状液体。微溶于水，溶于乙醇和乙醚。

Heptanoic acid, also called enanthic acid, is an organic compound composed of a seven-carbon chain terminating in a carboxylic acid. It is an oily liquid with an unpleasant, rancid odor. It contributes to the odor of some rancid oils. It is slightly soluble in water, but very soluble in ethanol and ether.