- A duct or walled passageway. Our word "duct" is a contraction of the Latin word "ductus" meaning "leading". The Romans, however, preferred the word "canalis" meaning "a pipe or gutter" for a conduit. The term "ductus" also refers a key arterial shunt (ductus) in fetal life. Before birth, blood pumped from the heart through the pulmonary artery toward the lungs is shunted into the aorta. This arterial shunt, a short vessel, is the ductus arteriosus. When the shunt is open, it is said to be patent. The ductus arteriosus usually closes at or shortly after birth, permitting blood from that moment on to course from the heart directly to the lungs. However, if the ductus arteriosus remains open (patent), flow reverses and blood from the aorta is shunted into the pulmonary artery and recirculated through the lungs. A patent ductus may close later spontaneously (on its own) or need to be ligated (tied off) surgically.
* * *- d. aberrantes SYN: aberrant ductules, under ductule.- d. arteriosus a fetal vessel connecting the left pulmonary artery with the descending aorta; in the first two months after birth, it normally changes into a fibrous cord, the ligamentum arteriosum; persistent postnatal patentcy is a correctable cardiovascular handicap. SYN: arterial canal, arterial duct, Botallo duct.- d. biliaris [TA] SYN: bile duct (2).- d. biliferi SYN: biliary ductules, under ductule.- d. caroticus a portion of the embryonic dorsal aorta between points of juncture with the third and fourth arch arteries; it disappears early in development. SYN: carotid duct.- d. cochlearis [TA] SYN: cochlear duct.- d. cysticus [TA] SYN: cystic duct.- d. deferens [TA] the secretory duct of the testicle, running from the epididymis, of which it is the continuation, to the prostatic urethra where it terminates as the ejaculatory duct. SYN: deferent canal, deferent duct, spermatic duct, spermiduct (1), testicular duct, vas deferens.- d. deferens vestigialis SYN: longitudinal duct of epoöphoron.- d. ejaculatorius [TA] SYN: ejaculatory duct.- d. endolymphaticus [TA] SYN: endolymphatic duct.- d. epididymidis [TA] SYN: duct of epididymis.- d. excretorius SYN: excretory duct.- d. excretorius glandulae vesiculosae [TA]- d. hemithoracicus SYN: hemithoracic duct.- d. hepaticus communis [TA] SYN: common hepatic duct.- d. incisivus [TA] SYN: incisive duct.- d. lactiferi [TA] SYN: lactiferous ducts, under duct.- d. lingualis a pit on the upper surface of the tongue at the apex of the sulcus terminalis; it marks the point of origin of the d. thyroglossus of the embryo; known more commonly as the foramen cecum.- d. nasolacrimalis [TA] SYN: nasolacrimal duct.- d. pancreaticus [TA] SYN: pancreatic duct.- d. paramesonephricus SYN: paramesonephric duct.- d. paraurethrales [TA] SYN: paraurethral ducts, under duct.- d. parotideus [TA] SYN: parotid duct.- patent d. arteriosus d. arteriosus.- d. perilymphaticus SYN: cochlear aqueduct.- d. pharyngobranchialis III a narrow communication between the third branchial pouch and the pharynx in the embryo.- d. pharyngobranchialis IV a narrow communication between the fourth branchial pouch and the pharynx in the embryo.- d. prostatici SYN: prostatic ductules, under ductule.- d. reuniens [TA] a short membranous tube passing from the lower end of the saccule to the cochlear duct of the membranous labyrinth. SYN: canaliculus reuniens, canalis reuniens, Hensen canal, Hensen duct, uniting canal, uniting duct.- d. saccularis [TA] SYN: saccular duct.- d. semicirculares [TA] SYN: semicircular ducts, under duct.- d. submandibularis [TA] SYN: submandibular duct.- d. submaxillaris SYN: submandibular duct.- d. sudoriferus SYN: duct of sweat glands.- d. thoracicus [TA] SYN: thoracic duct.- d. thyroglossus [TA] SYN: thyroglossal duct.- d. utricularis [TA] SYN: utricular duct.- d. utriculosaccularis [TA] SYN: utriculosaccular duct.- d. venosus in the fetus, continuation of the left umbilical vein through the liver to the vena cava inferior; after birth, its lumen becomes obliterated, forming the ligamentum venosum.- d. venosus arantii rarely used term for d. venosus.
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* * *n.
* * *duc·tus (dukґtəs) gen. and pl. ducґtus [L.] duct; a passage with well-defined walls. see also ductulus.
Descriptions of structures are given on TA terms, and include the anglicized names of specific ducts.
Medical dictionary. 2011.