Definition of butyric acid in US English:

butyric acid


  • A colorless, syrupy liquid organic acid found in rancid butter and in arnica oil.

    Alternative name: butanoic acid; chemical formula: C₃H₇COOH

    • ‘Undigested lactose fermented by bacteria creates lactic acid in the stool and other short chain fatty acids such as butyric acid.’
    • ‘A variety of other organic acids are produced by other bacteria, including butyric acid, responsible for the taste of rancid butter.’
    • ‘The culture supernatants were analysed and butyric acid identified as the potentially toxic material.’
    • ‘He named these materials and some of these names, like stearic acid and butyric acid, are still used today.’
    • ‘The name comes from butyric acid, an acid that has the smell of rancid butter.’


Mid 19th century: butyric from Latin butyrum (see butter) + -ic.


butyric acid

/byo͞oˌtirik ˈasid/