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ergosterol

[ur-gos-tuh-rohl, -rawl]
noun Biochemistry.
  1. a colorless, crystalline, water-insoluble sterol, C28H43OH, that occurs in ergot and yeast and that, when irradiated with ultraviolet light, is converted to vitamin D.

Origin of ergosterol

First recorded in 1885–90; ergo-2 + sterol
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ergosterol

ergosterol

noun
  1. a plant sterol that is converted into vitamin D by the action of ultraviolet radiation. Formula: C 28 H 43 OH
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
ergosterol in Medicine

ergosterol

[ûr-gŏs′tə-rôl′, -rōl′]
n.
  1. A crystalline sterol synthesized by yeast from sugars or derived from ergot and converted to vitamin D2 when exposed to ultraviolet radiation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.