Vas deferens

The Male Anatomy

The vas deferens (also called the ductus deferens) is part of the human male anatomy. It is the main duct through which semen travels during ejaculation. It connects the epididymis to the ejaculatory duct. It's name is Latin, literally meaning "carrying-away vessel"

During ejaculation, the wall of the vas deferens thickens and thins itself, thus propelling the sperm.