ˈtestə̇s noun
( plural tes·tes -eˌstēz)
Etymology: Latin, witness, testis; perhaps from its being evidence of maleness — more at testament
1. : a male reproductive gland that usually consists largely of convoluted tubules from the epithelium of which spermatozoa develop, that corresponds to the ovary of the female and in craniate vertebrates is usually paired and developed 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
2. : either of the inferior corpora quadrigemina