Epididymis

The epididymis (/ɛpᵻˈdɪdᵻmɪs/; plural: epididymides /ɛpᵻdᵻˈdɪmədiːz/ or /ɛpᵻˈdɪdəmɪdiːz/) is a tube that connects a testicle to a vas deferens in the male reproductive system. It is present in all male reptiles, birds, and mammals. It is a single, narrow, tightly-coiled tube (in adult humans, six to seven feet in length) connecting the efferent ducts from the rear of each testicle to its vas deferens.