What does estrogen mean?
Estrogen refers to any of a group of steroid hormones that play a central role in the development and regulation of the female reproductive system. Produced mainly by the ovaries — with smaller amounts made by the adrenal glands and fat tissue — these hormones drive the physical changes of puberty, regulate the menstrual cycle, support pregnancy, and maintain bone density and cardiovascular health. The most abundant and potent form is estradiol, though estriol and estrone are also important at different life stages. In everyday usage, the word appears frequently in medical and wellness contexts: doctors may test a patient's estrogen levels, discuss estrogen replacement therapy during menopause, or explain how certain cancers are sensitive to estrogen. Though primarily a scientific term, it is common in general conversation about women's health. The word derives from 'estrus' (fertility or sexual receptivity) combined with a Greek root meaning to produce or generate.
nounAny of a group of steroid hormones, produced chiefly by the ovaries, that promote the development and maintenance of female secondary sexual characteristics and regulate the menstrual cycle and reproductive system.
- Any of a group of steroid hormones responsible for female secondary sexual characteristics and regulation of the reproductive cycle.
- (In plural, or as a mass term) Such hormones collectively, considered in relation to their physiological or medical effects.
"After menopause, the body's production of estrogen declines sharply."
"Rising estrogen levels trigger the thickening of the uterine lining each month."
"The doctor discussed whether hormone therapy containing estrogen would be appropriate for her symptoms."
The plural is used when referring to multiple distinct types or forms of estrogen (such as estradiol, estriol, and estrone), rather than to quantity of the hormone itself.
"There are three major naturally occurring estrogens in humans: estradiol, estriol, and estrone."
The word estrogen literally means 'the frenzy generator' — it was coined from 'estrus', the Greek-derived term for the fertile heat of animals.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of estrogen
The term 'estrogen' was coined in the early twentieth century from 'estrus', itself derived from Greek 'oistros' meaning frenzy or gadfly, referring to the fertile period of female animals, combined with '-gen', from a Greek root meaning to beget or produce. It entered English as scientists identified the hormones responsible for female sexual characteristics. The spelling 'oestrogen' reflects the Greek-derived diphthong and remains standard in British English, while American English simplified it to 'estrogen'.
How estrogen is actually used
Primarily a scientific and medical term, but widely used in everyday health discussions. Spelled 'oestrogen' in British English and 'estrogen' in American English; both are fully accepted within their respective regions. Used almost exclusively as an uncountable noun.
Easily confused with estrogen
Estradiol is one specific and the most potent form of estrogen, whereas estrogen is the general term for the whole class of related hormones.
Testosterone is the principal male sex hormone (an androgen), while estrogen is the principal class of female sex hormones.