Main Entry: tes·tos·ter·one

Pronunciation: \tes-ˈtäs-tə-ˌrōn\

Function: noun

Etymology: testis + -o- + -sterone

Date: 1935

1 : a hormone that is a hydroxy steroid ketone C₁₉H₂₈O₂ produced especially by the testes or made synthetically and that is responsible for inducing and maintaining male secondary sex characters
2 : qualities (as brawn and aggressiveness) usually associated with males : manliness