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Medicine & BodyGreekEnglish

Estrogen

/ˈɛstrədʒən/noun

Any of the steroid hormones, chiefly estradiol, that drive female sexual development and regulate the menstrual cycle.

The Greek roots

οἶστρος
oîstros
gadfly, frenzy
+
-γενής
-genḗs
producing

Literally: producing frenzy

The story of the word

Oistros was the biting fly that maddened cattle, and Aeschylus uses it for the gadfly that drove Io across the world. Zoologists took it for oestrus, the period when an animal is receptive to mating, and the hormone was named in the 1920s for producing that state. American spelling dropped the oe, which hides the fly completely.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
20th century

Same family

oestrusandrogenestradioloestrous

In a sentence

Estrogen levels fall sharply at menopause.

The trial compared transdermal estrogen with the oral form.

Built on the same root

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