Oestradiol

n. female sex hormone which is secreted by the ovaries and is responsible for the development and maintenance of the female sexual characteristics, oestrogen

Estradiol (17β-estradiol) (also oestradiol) is a sex hormone. Labelled the "female" hormone but also present in males, it represents the major estrogen in humans. Estradiol has not only a critical impact on reproductive and sexual functioning, but also affects other organs including bone structure.
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Estradiol /es·tra·di·ol/ the most potent estrogen in humans; pharmacologically, it is often used in the form of its esters or as a semisynthetic [more]Oestradiol - Community and Resources

Noun
1. the most powerful female hormone that occurs naturally; synthesized and used to treat estrogen deficiency and breast cancer
(synonym) estradiol
(hypernym) estrogen, oestrogen
(substance-holonym) Loestrin

n. oestradiol, hormone