testosterone
//tɛˈstɒstəˌroʊn//
Noun
1
A steroid hormone produced primarily in the testes that stimulates the development of male secondary sexual characteristics and regulates male reproductive function.
Testosterone levels naturally decline as men age.
2
Qualities or behaviors stereotypically associated with masculinity, such as aggression, competitiveness, or physical strength.
There was too much testosterone in the room during the heated debate.