noun

• (British spelling, biochemistry, steroids) Alternative spelling of estrone. [(American spelling, biochemistry, steroids, pharmacology) A natural estrogenic hormone that is a ketone C₁₈H₂₂O₂ found in the body chiefly as a metabolite of and less potent than estradiol, that is also secreted especially by the ovaries, and that is used to treat various conditions (such as ovarian failure and menopausal symptoms) relating to estrogen deficiency.]