ductus

Duct.

Pl. ductus [L.] duct.

• d. arteriosus — a fetal blood vessel that joins the aorta and pulmonary artery. Abnormal persistence of an open lumen after birth results in a patent ductus arteriosus. Called also persistent or patent ductus arteriosus.
• d. choledochus — see bile duct.
• d. deferens — the excretory duct of the testis, which in horses and ruminants joins the excretory duct of the seminal vesicle to form the ejaculatory duct; called also vas deferens.
• d. epididymis — the duct which, in combination with connective tissue and muscle, forms the head, body and tail of the epididymis and continues as the ductus deferens.
• d. epoophori longitudinales — see gartner's ducts.
• d. reuniens — the joining channel between the cochlea and sacculus of the membranous labyrinth of the inner ear.
• d. venosus — a major blood channel that develops through the embryonic liver from the left umbilical vein to the caudal vena cava and closes within a few days after birth. If it remains patent, a congenital portacaval anastamosis is created.