ep·i·did·y·mis / ˌepiˈdidəməs/ • n. (pl. -did·y·mi·des / -ˈdidəmiˌdēz; -diˈdimiˌdēz/ ) Anat. a highly convoluted duct behind the testis, along which sperm passes to the vas deferens.DERIVATIVES: ep·i·did·y·mal / -məl/ adj.

epididymis A long coiled tube in which spermatozoa are stored in vertebrates. In reptiles, birds, and mammals it is attached at one end to the testis and opens into the sperm duct (vas deferens) at the other.

epididymis (epi-did-i-mis) n. (pl. epididymides) a highly convoluted tube, about seven metres long, that connects the testis to the vas deferens. The spermatozoa are moved along the tube and are stored in the lower part until ejaculation.
—epididymal adj.