white, solid substance present in body tissues, 1894, earlier cholesterin, from French cholestrine (Chevreul, 1827), from Greek khole "bile" (see cholera) + steros "solid, stiff" (see sterility). So called because originally found in gallstones (Conradi, 1775). The name was changed to the modern form (with chemical suffix -ol, denoting an alcohol) after the compound was discovered to be a secondary alcohol.