testosterone

n. male sexual hormone

Testosterone is a steroid hormone from the androgen group. Testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid. In both males and females, it plays key roles in health and well-being. Examples include enhanced libido, energy, immune function, and protection against osteoporosis. On average, an adult human male body produces about eight to ten times more testosterone than an adult female body. Testosterone is found in numerous animals.
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Testosterone /tes·tos·te·rone/ the principal androgenic hormone, produced by the interstitial cells of the testes in response to stimulation by the [more]Testosterone - Community and Resources

Noun
1. a potent androgenic hormone produced chiefly by the testes; responsible for the development of male secondary sex characteristics
(hypernym) androgen, androgenic hormone

n. testosterone, male sexual hormone