epididymis

n. (Anatomy) system of testicular tubules leading to the vas deferens

The epididymis is part of the human male reproductive system and is present in all male mammals. It is a narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens.
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Epididymis /ep·i·did·y·mis/ pl. epididy´mides [Gr.] an elongated cordlike structure along the posterior border of the testis; its coiled duct [more]Epididymis - Community and Resources

Noun
1. a convoluted tubule in each testis; carries sperm to vas deferens
(hypernym) duct, epithelial duct, canal, channel
(part-holonym) seminal duct
(part-meronym) vasa efferentia

(n.)
An oblong vermiform mass on the dorsal side of the testicle, composed of numerous convolutions of the excretory duct of that organ.