a plant sterol that is converted into vitamin D by the action of ultraviolet radiation. Formula: C28H43OH
ergosterol in American English
(ɜrˈgɑstərˌɔl; ɜrˈgɑstərˌoʊl)
noun
a crystalline plant sterol, C28H43OH, formerly prepared from ergot but now chiefly from yeast: when exposed to ultraviolet rays it produces a vitamin (D2) used to prevent or cure rickets