English Reference

Word

testosterone

Phoneticstestos·terone

US/ˌtɛsˈtɑstɝˌoʊn/

UK/tɛstˈɒstəɹˌəʊn/

Definitions

01the hormone

B2 · Medicine

n. a natural chemical in the body that helps develop muscles, a deep voice, and other male features.

n. a steroid hormone that stimulates the development of male secondary sexual characteristics, produced primarily in the testes.

“The doctor checked his testosterone levels to see why he felt so tired.”

“Synthetic testosterone is sometimes prescribed to patients with hormonal deficiencies, though its use must be strictly monitored by a specialist.”

Technical

Usage

Uncountable in general contexts; countable when referring to specific types or measurements.

Synonyms

Antonyms

02aggressive behavior

C1

n. behavior that is very aggressive, competitive, or risky, often associated with men.

n. a figurative reference to qualities of aggression, competitiveness, or bravado traditionally associated with masculinity.

“The meeting was full of testosterone, with everyone shouting to prove they were right.”

“The locker room was thick with testosterone as the players prepared for the championship final, their adrenaline-fueled shouting echoing off the walls.”

Informal

Teaching tip

This sense is often used with a slightly negative or critical tone to describe men acting in an overly competitive or foolish way.

Synonyms

Real-World Examples

“Men with lower-pitched voices have higher testosterone and greater upper-body strength.”
Phys.org · 18 Aug 2026
“Will the US army benefit from testing its male soldiers for testosterone levels?”
BBC News · 23 Jul 2026

Etymology

From test(is) + -o- + -sterone (“steroid hormone”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry

Level
B2 · Upper Intermediate
Frequency
Frequent
Updated

Scan code

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