'Testosterone' definitions:

Definition of 'testosterone'

From: WordNet
noun
A potent androgenic hormone produced chiefly by the testes; responsible for the development of male secondary sex characteristics

Definition of 'Testosterone'

From: GCIDE
  • Testosterone \Tes*tos"ter*one\ (t[e^]s*t[o^]s"t[~e]r*[=o]n), n. [testes + o + sterone a steroid ketone.] a steroid hormone (C19H28O2) produced mostly in the testes, which is responsible for producing the secondary sexual characteristics of males. [PJC]