Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics by binding to androgen receptors. Androgens modulate the activity of the male sex organs and the development of male secondary sex characteristics. They are also the precursor of all estrogens, the female sex hormones.
The primary and most well-known androgen is testosterone. Besides testosterone, other androgens include: Dehydroepiandrosterone (DHEA); Androstenedione (Andro); Androsterone; and Androstenediol.