testis

tes·tis

noun \ˈtes-təs\

plural tes·tes \ˈtes-ˌtēz\

Definition of TESTIS

: a typically paired male reproductive gland that usually consists largely of seminiferous tubules from the epithelium of which spermatozoa develop, that contains androgen-secreting Leydig cells in the interstitial tissue, that corresponds to the ovary of the female and in craniate vertebrates develops from the genital ridges of the embryo, and that in most mammals descends into the scrotum before the attainment of sexual maturity and in many cases before birth

Illustration of TESTIS