estrogen

American  

[es-truh-juhn] / ˈɛs trə dʒən /

noun

Biochemistry.

estrogens plural

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

• antiestrogen
  noun
• estrogenic
  adjective
• estrogenically
  adverb

Inflected Forms

Nouns

• estrogens
  plural

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

This is because estrogen helps protect bones by slowing the natural process of bone breakdown.

From Science Daily • Jun. 25, 2026

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

As of right now, dermatologists don’t know the root cause of FAPD, though they believe it might show up in midlife due to a decline in estrogen, which protects against hair follicle inflammation.

From Slate • May 23, 2026

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

From Salon • May 13, 2026

Gail, for example, was doing fine, healthwise anyway, until she ran out of money for estrogen pills.

From "Nickel and Dimed: On (Not) Getting By in America" by Barbara Ehrenreich