estrogen

American  

[es-truh-juhn] / ˈɛs trə dʒən /

noun

Biochemistry.

1. any of several major sex hormones produced primarily by the ovarian follicles of mammals, capable of inducing estrus, developing and maintaining secondary female sex characteristics, and preparing the uterus for the reception of a fertilized egg: used, especially in synthetic form, as a component of oral contraceptives, in certain cancer treatments, and in other therapies.

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estrogen British  

/ ˌɛstrəˈdʒɛnɪk, ˈɛstrədʒən, ˌiːstrə-, ˈiːstrə- /

noun

1. the usual US spelling of oestrogen

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estrogen Scientific  

/ ĕs′trə-jən /

1. Any of a group of steroid hormones that primarily regulate the growth, development, and function of the female reproductive system. The main sources of estrogen in the body are the ovaries and the placenta. Estrogen-like compounds are also formed by certain plants.

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estrogen Cultural  

1. A group of hormones, secreted mainly by the ovaries, that influence the female reproductive system in many ways, notably in preparing the body for ovulation and in the development of female secondary sex characteristics.

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Other Word Forms

Derived Forms

• estrogenic
  adjective
• antiestrogen
  noun
• estrogenically
  adverb

Etymology

Origin of estrogen

First recorded in 1925–30; estr(us) + -o- + -gen

Explanation

Estrogen is a hormone that occurs naturally in humans and is also used in medications and treatments. Men and women both have a balance of estrogen and testosterone. People who are biologically female, with XX chromosomes, typically have a high level of estrogen and a lower level of testosterone once they reach puberty. It's the opposite in biological males. These sex hormones are responsible for the physical changes associated with the reproductive system. Estrogen is used in medications and therapeutic treatments too.

Example Sentences

Soy isoflavones belong to a group of compounds called flavonoids and can mimic some actions of the hormone estrogen.

From Science Daily • May 30, 2026

Kirkwood says this may be related to their smaller body size and declining estrogen levels, which could limit how tissues respond to anti-inflammatory changes.

From Science Daily • May 19, 2026

The push was successful: Last fall, the FDA removed safety warnings from menopause treatments containing estrogen.

From Salon • May 13, 2026

And the secret in the secret sauce of HRT is estrogen.

From MarketWatch • May 12, 2026

It is possible to have liver damage sufficient to interfere with estrogen elimination without detection of the damage by any tests now available to the medical profession.

From "Silent Spring" by Rachel Carson