The ductus deferens, or the vas deferens, is a male anatomical part that is a long, muscular tube that travels from the epididymis into the pelvic cavity, to just behind the bladder.
The vas deferens transports mature sperm to the urethra in preparation for ejaculation.
It is a continuation of the epididymis and is involved in transporting spermatozoa from the epididymis to the ejaculatory ducts.