cholesterol (n.)

white, solid substance present in body tissues, 1894, earlier cholesterin, from French cholestrine (Chevreul, 1827), from Latinized form of Greek khole "bile" (from PIE root *ghel- (2) "to shine," with derivatives denoting "green, yellow," and thus "bile, gall") + steros "solid, stiff" (from PIE root *ster- (1) "stiff"). 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.