: 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.
The research proposes that flavonoids and saponins in legumes may have greater effects involving testosterone, while compounds in cruciferous vegetables could interact more strongly with estrogen and progesterone pathways. Paul McClure 23, New Atlas, 23 Aug. 2026 Drugmakers continue to face severe supply constraints for transdermal estrogen patches as demand surges, The Hill writes. Ed Silverman, STAT, 21 Aug. 2026 Common ones focus on stress hormones like cortisol or reproductive hormones like estrogen, luteinizing hormone, progesterone, and testosterone. Cathy Cassata, HEALTH, 21 Aug. 2026 As estrogen levels fluctuate and eventually decline during perimenopause and menopause, those changes may affect how the brain functions. Lauryn Higgins, Flow Space, 19 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

Browse Nearby Words

Cite this Entry

“Estrogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/estrogen. Accessed 25 Aug. 2026.

Kids Definition

estrogen

noun
: 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
variants or chiefly British oestrogen
: 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
an estrogen-like compound
estrogen-like effects

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