# estrogen

/ˈɛstɹədʒən/ (US) · CEFR C1 · Noun

Source: https://englishreference.com/word/estrogen
Updated: 2026-05-06

## Definition

a hormone in the body that is responsible for developing female physical features. Both men and women have it, but women have much higher levels.

For teachers: a primary female sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. Produced mainly by the ovaries, though present in smaller quantities in males.

## Examples

- The doctor checked her estrogen levels during the checkup.
- During menopause, the body produces less estrogen, which can lead to various physical changes and symptoms.
- Research indicates that estrogen plays a crucial role not only in reproductive health but also in maintaining bone density and cardiovascular function throughout a person's life.

## Usage notes

- Commonly used in medical and biological contexts; spelled 'oestrogen' in British English.

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