estrogen

noun

es·​tro·​gen ˈe-strə-jən How to pronounce estrogen (audio)
: any of various natural steroids (such as estradiol) that are formed from androgen precursors, that are secreted chiefly by the ovaries, placenta, adipose tissue, and testes, and that stimulate the development of female secondary sex characteristics and promote the growth and maintenance of the female reproductive system
also : any of various synthetic or semisynthetic steroids (such as ethinyl estradiol) that mimic the physiological effect of natural estrogens

Examples of estrogen in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Research generally shows that transdermal estrogen — delivered through a patch — is less likely to cause blood clots than oral estrogen. — Mara Gordon, NPR, 7 Aug. 2026 Although it hasn’t been studied in humans, pre-clinical research in female rodents suggests that lower estrogen levels translated to duller behavioral responses to psilocybin and higher levels caused more intense effects. — Helen Carefoot, Flow Space, 5 Aug. 2026 That's because of the hormonal shift and decrease of estrogen in menopause. — Norah O'Donnell, CBS News, 5 Aug. 2026 Adipose tissue converts androgens into estrogen, so rapid fat loss shifts circulating estrogen quickly. — Jesse Pines, Forbes.com, 4 Aug. 2026 See All Example Sentences for estrogen

Word History

Etymology

estrus + -o- + -gen

Note: The word estrogen was originally a U.S. brand name for an extract of glandular tissue used in the treatment of ovarian dysfunction. Its producer, Parke, Davis and Company, relinquished rights to the name in 1936.

First Known Use

1927, in the meaning defined above

Time Traveler
The first known use of estrogen was in 1927

Phrases Containing estrogen

Browse Nearby Words

estriol
estrogen
estrogenic
See all Nearby Words

Cite this Entry

“Estrogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/estrogen. Accessed 11 Aug. 2026.

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Kids Definition

estrogen

noun
es·​tro·​gen ˈes-trə-jən How to pronounce estrogen (audio)
: a substance that tends to cause the development of secondary sex characteristics in the female and promote the growth and normal functioning of the female reproductive system
estrogenic
ˌes-trə-ˈjen-ik
adjective

Medical Definition

estrogen

noun
es·​tro·​gen ˈes-trə-jən How to pronounce estrogen (audio)
variants or chiefly British oestrogen
ˈē-strə-jən How to pronounce estrogen (audio)
: any of various natural steroids (as estradiol) that are formed from androgen precursors, that are secreted chiefly by the ovaries, placenta, adipose tissue, and testes, and that stimulate the development of female secondary sex characteristics and promote the growth and maintenance of the female reproductive system
also : any of various synthetic or semisynthetic steroids (as ethinyl estradiol) that mimic the physiological effect of natural estrogens
estrogen-like adjective
or estrogenlike
-ˌlīk How to pronounce estrogen (audio)
an estrogen-like compound
estrogen-like effects

More from Merriam-Webster on estrogen

Nglish: Translation of estrogen for Spanish Speakers

Britannica.com: Encyclopedia article about estrogen

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