ergosterolPronunciation: /əːˈgɒstərɒl/Definition of ergosterol noun [mass noun] Biochemistry a compound present in ergot and many other fungi. A steroid alcohol, it is converted to vitamin D2 when irradiated with ultraviolet light. Origin: early 20th century: from ergot, on the pattern of cholesterolergosterol in other Oxford dictionaries Definition of ergosterol in the US English dictionary
