hircic acid noun1 •(historical) A type of oily acid (a mixture rich in capric- and caproic acids) made from mutton suet, having an odor similar to that of a goat, used in the early days of the production of soap, and in soup-making.Hircic acid is the odorous principle of soap, made of mutton suet, and it exists in so very small quantity....Its smell resembles that of a goat — 1824
