sterol Any of a group of steroid-based alcohols having a hydrocarbon side-chain of 8–10 carbon atoms. Sterols exist either as free sterols or as esters of fatty acids. Animal sterols (zoosterols) include cholesterol and lanosterol. The major plant sterol (phytosterol) is beta-sitosterol, while fungal sterols (mycosterols) include ergosterol.

ste·rol / ˈsterôl; -äl; ˈsti(ə)r-/ • n. Biochem. any of a group of naturally occurring unsaturated steroid alcohols, typically waxy solids.

sterol (steer-ol) n. one of a group of steroid alcohols. The most important sterols are cholesterol and ergosterol.