Medical Definition of Testis
Testis: The male sex gland, located behind the penis in a pouch of skin called the scrotum. The testes produce and store sperm and are also the body's main source of male hormones, such as testosterone. These hormones control the development of the reproductive organs and other male characteristics, such as body and facial hair, low voice, and wide shoulders. Also known as testicle.
Quick GuideScreening Tests Every Man Should Have
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