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oestrone

British  
/ ˈɛstrəʊn, ˈiːstrəʊn /

noun

  1. a weak oestrogenic hormone secreted by the mammalian ovary and having the same medical uses as oestradiol. Formula: C 18 H 22 O 2

"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

Etymology

Origin of oestrone

C20: from oestr ( us ) + -one