Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
a passage with well-defined walls, especially a tubular structure for the passage of excretions or secretions. adj., adj ductal.
accessory duct of Santorini a tubular structure that drains the lower part of the head of the pancreas.
alveolar d's small passages connecting the respiratory bronchioles and the alveolar sacs.
Bartholin's duct (duct of Bartholin) the larger and longer of the sublingual ducts.
bile d's (biliary d's) see bile ducts.
cochlear duct a spiral membranous tube in the bony canal of the cochlea between Reissner's membrane and the basilar membrane; it is divided into the scala tympani, scala vestibuli, and spiral lamina. Called also scala media.
common bile duct a duct formed by the union of the cystic and hepatic ducts; see also bile ducts.
cystic duct the passage connecting the gallbladder neck and the common bile duct.
efferent duct any duct that gives outlet to a glandular secretion.
ejaculatory duct the duct formed by union of the ductus deferens and the duct of the seminal vesicles, opening into the prostatic urethra on the colliculus seminalis.
endolymphatic duct a canal connecting the membranous labyrinth of the ear with the endolymphatic sac.
excretory duct one through which the secretion is conveyed from a gland.
hepatic duct the excretory duct of the liver, or one of its branches in the lobes of the liver; see also bile ducts.
lacrimal duct the excretory duct of the lacrimal gland; see also lacrimal apparatus. Called also lacrimal canaliculus.
lacrimonasal duct nasal duct.
lactiferous d's ducts conveying the milk secreted by the lobes of the breast to and through the nipples.
lymphatic duct, left thoracic duct.
lymphatic d's see lymphatic ducts.
mammary duct lactiferous ducts.
mesonephric duct an embryonic duct of the mesonephros, which in the male becomes the epididymis, ductus deferens and its ampulla, seminal vesicles, and ejaculatory duct, and in the female is largely obliterated.
müllerian duct either of the two paired embryonic ducts developing into the vagina, uterus, and fallopian tubes, and becoming largely obliterated in the male.
nasal duct (nasolacrimal duct) the downward continuation of the lacrimal sac, opening on the lateral wall of the inferior meatus of the nose; see also lacrimal apparatus.
pancreatic duct the main excretory duct of the pancreas, which usually unites with the common bile duct before entering the duodenum at the major duodenal papilla; see also bile ducts.
papillary d's straight excretory or collecting portions of the renal tubules, which descend through the renal medulla to a renal papilla.
paramesonephric duct müllerian duct.
paraurethral d's Skene's glands.
parotid duct the duct by which the parotid glands empty into the mouth.
prostatic d's minute ducts from the prostate, opening into or near the prostatic sinuses on the posterior wall of the urethra.
lymphatic duct, right a vessel draining lymph from the upper right side of the body, receiving lymph from the right subclavian, jugular, and mediastinal trunks when those vessels do not open independently into the right brachiocephalic vein.
salivary d's the ducts of the salivary glands.
semicircular d's the long ducts of the membranous labyrinth of the ear.
seminal d's the passages for conveyance of spermatozoa and semen.
sublingual d's the excretory ducts of the sublingual salivary glands.
submandibular duct (submaxillary duct) the duct that drains the submandibular gland and opens at the sublingual caruncle.
tear duct lacrimal duct.
thoracic duct a duct beginning in the cisterna chyli and emptying into the venous system at the junction of the left subclavian and left internal jugular veins. It acts as a channel for the collection of lymph from the portions of the body below the diaphragm and from the left side of the body above the diaphragm.
a duct in the embryo draining the mesonephric tubules in the mesonephros; in the male, it becomes the ductus deferens; in the female, it becomes vestigial.
See also: longitudinal duct of epoophoron.
See also: longitudinal duct of epoophoron.
Etymology: Gk, mesos + nephros, kidney; L, ducere, to lead
(in embryology) a duct that in the male gives rise to the ducts of the reproductive system (ductus epididymidis, ductus deferens, seminal vesicle, ejaculatory duct). In the female it persists vestigially as Gartner's duct. Also called wolffian duct.
mes·o·neph·ric duct(mez'ō-nef'rik dŭkt)
A duct in the embryo draining the mesonephric tubules; in the male, it becomes the ductus deferens and ureter; in the female, it becomes the ureter's vestigial structures.
Synonym(s): wolffian duct.
Synonym(s): wolffian duct.
duct(dukt) [L. ductus, conveyance (for water)]
1. A narrow tubular vessel or channel, esp. one that conveys secretions from a gland.
2. A narrow enclosed channel containing a fluid, e.g., the semicircular duct of the ear.
accessory pancreatic duct
A duct of the pancreas leading into the pancreatic duct or the duodenum near the mouth of the common bile duct. Synonym: duct of Santorini
An obsolete term for the thoracic duct.
A branch of a respiratory bronchiole that leads directly to the alveolar sacs of the lungs.See: alveolus for illus
Bartholin ductSee: Bartholin, Caspar (the younger)
Any of the intercellular passages that convey bile from the liver to the hepatic duct, which joins the duct from the gallbladder (cystic duct) to form the common bile duct (ductus choledochus), and which enters the duodenum about 3 in (7.6 cm) below the pylorus.Synonym: biliary duct See: illustration
biliary ductBile duct.
Botallo ductDuctus arteriosus.
cochlear ductCochlear spiral canal.
common bile duct
The duct that carries bile and pancreatic juice to the duodenum. It is formed by the union of the cystic duct of the gallbladder and the hepatic duct of the liver and is joined by the main pancreatic duct.Synonym: ductus choledochus See: biliary tract for illus
The secretory duct of the gallbladder. It unites with the hepatic duct from the liver to form the common bile duct. See: biliary tract for illus
Any of a group of 12 to 14 small tubes that constitute the efferent ducts of the testis. They lie within the epididymis and connect the rete testis with the ductus epididymidis. Their coiled portions constitute the lobuli epididymidis.
The duct that conveys sperm from the vas deferens and secretions from the seminal vesicle to the urethra.
In the embryo, a tubular projection of the otocyst ending in a blind extremity, the endolymphatic sac. In the adult, it connects the endolymphatic sac with the utricle and saccule of the inner ear.
duct of the epoophoronGartner's duct.
Any duct that conveys a waste product from an organ, such as the collecting duct of the renal tubule.
Gartner ductSee: Gartner, Hermann
Either of the ducts that receive bile from the right or left lobe of the liver and carries it to the common bile duct. Synonym: ductus hepaticus dexter; ductus hepaticus sinister
Any of several short, narrow ducts that lie between the secretory ducts and the terminal alveoli in the parotid and submandibular glands and in the pancreas.
A duct passing between lobules within a gland, e.g., one of the ducts carrying bile.
Any of the small excretory ducts of the lacrimal glands.
Any of 15 to 20 ducts that drain the lobes of the mammary gland. Each opens in a slight depression in the tip of the nipple.Synonym: milk duct
Either of two main ducts conveying lymph to the bloodstream: the left lymphatic (thoracic) and the right lymphatic duct, which drains lymph from the right side of the body above the diaphragm. It discharges into the right subclavian vein. It is smaller than the left lymphatic duct.See: thoracic duct; illustration
mesonephric ductWolffian duct.
milk ductLactiferous duct.
Either of the bilateral embryonic tubes in the embryo from which the oviducts, uterus, and vagina develop in the female; in the male, they atrophy. Synonym: Müller duct
A membranous tube that runs in the nasolacrimal canal and drains tears from the lacrimal sac to the nasal cavity. It opens beneath the inferior nasal concha.
omphalomesenteric ductYolk stalk.
The duct that conveys pancreatic juice to the common bile duct and duodenum. Synonym: duct of Wirsung
Any of the large ducts formed by the uniting of the collecting tubules of the kidney; it empties into the renal pelvis.
papillary duct of BelliniSee: Bellini, Lorenzo
The genital canal in the embryo. In females it develops into the oviducts, uterus, and vagina; in males it degenerates to form the appendix testis.
paraurethral ductSkene duct.
parotid ductStensen duct.
One of about 20 ducts that discharge prostatic secretion into the urethra. Synonym: duct prostaticus
duct of RivinusSee: Rivinus, August
Any of the ducts that drain a salivary gland.
duct of SantoriniAccessory pancreatic duct.
Any of the smaller canals of a gland.
One of a pair of embryonic tubes located between the visceral and parietal layers of the mesoblast on each side of the body.
One of three membranous tubes forming a part of the vestibular labyrinth of the inner ear. They lie within the semicircular canals and bear corresponding names: anterior, posterior, and lateral. The semicircular ducts originate from the utricle as a single common tube (crus communale). The three ducts then branch, and each follows the course of a different bony semicircular canal. At their far ends the ducts widen into an ampulla that contains a specialized endothelium that is sensitive to motion of the endolymph. Axons from receptor cells in these sensory epithelia transmit motion information to the brain via the vestibular division of the vestibulococchlear nerve (CN VIII). See: labyrinth for illus.
Any of the ducts that convey sperm, specifically the ductus deferens and the ejaculatory duct.
Skene ductSee: Skene, Alexander
The secretory duct of the testicle that later joins the duct of the seminal vesicle to become the ejaculatory duct. Synonym: ductus deferens; vas deferens; testicular duct
Stensen ductSee: Stensen, Niels
Any of a class of ducts within the lobules of glands, esp. salivary glands, that contain radially appearing striations within the cells, denoting the presence of mitochondria.
Any of the secretory ducts of the sublingual gland.See: Bartholin duct
A duct that conveys tears. These include secretory ducts of lacrimal glands, and lacrimal and nasolacrimal ducts.
testicular ductSpermatic duct.
The main lymphatic duct, originating at the cisterna chyli. It passes upward through the diaphragm into the thorax and continues upward along the aorta and esophagus to the neck, where it turns to the left and enters the left subclavian vein near its junction with the left internal jugular vein. It receives lymph from all parts of the body except the right side of the head, neck, thorax, and upper extremity. See: lymphatic system for illus
In the embryo, a duct that connects the thyroid diverticulum with the tongue. It eventually disappears, its point of origin being indicated as a pit, the foramen cecum. It sometimes persists as an anomaly.
umbilical ductYolk stalk.
A narrow tube emanating from the utricle, connecting it to the saccule, and opening into the endolymphatic duct of the inner ear.
vitelline ductYolk stalk.
In the embryo, the duct leading from the mesonephros to the cloaca. From it develop the ductus epididymis, ductus deferens, seminal vesicle, ejaculatory duct, ureter, and pelvis of the kidney.Synonym: mesonephric duct
Wolff,Kaspar F., German embryologist in Russia, 1733-1794.
wolffian body - one of three excretory organs appearing in the evolution of vertebrates. Synonym(s): canal of Oken; corpus of Oken; mesonephros
wolffian cyst - a cyst lying in the broad ligaments of the uterus and arising from any mesonephric structures.
wolffian duct - a duct in the embryo draining the mesonephric tubules. Synonym(s): mesonephric duct
wolffian rest - remnants of the wolffian duct in the female genital tract that give rise to cysts. Synonym(s): mesonephric rest
wolffian ridge - one of the paired longitudinal ridges developing in the dorsal body wall of the embryo. Synonym(s): urogenital ridge
wolffian tubules - Synonym(s): Kobelt tubules
a passage with well-defined walls, especially a tubular structure for the passage of excretions or secretions. See also ductus.
accessory pancreatic duct
the duct of the dorsal pancreatic primordium that opens on the minor duodenal papilla. Called also Santorini's duct or duct of Santorini.
one of the final branches of the bronchial tree consisting of a tube whose walls are composed of alveoli.
bile duct, biliary duct
the passages for the conveyance of bile in and from the liver. See also bile duct.
a spiral membranous tube in the bony canal of the cochlea divided into the scala tympani, scala vestibuli and spiral lamina.
common bile duct
a duct formed by the union of the cystic and hepatic ducts. See also bile duct.
the passage connecting the gallbladder neck and the bile duct.
any duct that gives outlet to a glandular secretion.
the duct formed by union of the ductus deferens and the duct of the seminal vesicles, opening into the prostatic urethra on the colliculus seminalis. Found in the horse and ruminants.
a canal connecting the membranous labyrinth of the ear with the endolymphatic sac.
developed from the first part of the mesonephric duct.
one through which the secretion is conveyed from a gland.
duct of Gartner
see gartner's ducts.
the excretory duct of the liver, or one of its branches in the lobes of the liver. See also bile duct.
one of a pair of ducts perforating the palate and which communicate between the mouth and the nasal cavity; they are thought to conduct chemicals for olfactory appraisal by the vomeronasal organ.
ducts within lobes which provide drainage for secretions of lobes of glands.
ducts found within lobules which provide drainage for secretions of lobules of glands.
one of the excretory ducts of the lacrimal gland. See also lacrimal apparatus.
ducts conveying the milk secreted by the lobes of the mammary gland to the lactiferous sinuses or to the teats.
drains the secretions from the lobes of gland, connecting with the main excretory duct.
drains the secretions of lobules of glands.
larger lymph drainage vessels, e.g. thoracic duct.
lymphatic duct (left)
lymphatic duct (right)
a vessel draining lymph from the cranial right side of the body, receiving lymph from the right subclavian, jugular and mediastinal trunks when those vessels do not open independently into the right brachiocephalic vein.
drainage duct of the mandibular salivary gland.
see mesonephric duct.
the embryonic ureter.
see müllerian duct.
the duct leading from the lacrimal sac, opening on the floor of the nasal vestibule. Called also nasolacrimal duct. See also lacrimal apparatus.
see nasal duct (above).
see incisive duct (above).
the main excretory duct of the pancreas, which usually opens with the bile duct on the major duodenal papilla; may be a single duct, or two ducts which join, or two independent ducts opening into opposite sides of the intestine. See also bile duct. Called also Wirsung's duct.
papillary d's (kidney)
the straight excretory or collecting portions of the renal tubules, which descend through the renal medulla to a renal papilla or renal crest.
papillary duct (teat)
see teat canal.
the duct by which the parotid gland empties into the mouth vestibule opposite the upper molars. See also parotid glands.
see aqueduct of cochlea.
the early embryonic duct from the primitive kidney which leads into the mesonephric duct in the embryo's later stages.
minute ducts from the prostate, opening into or near the prostatic sinuses on the dorsal wall of the urethra.
the ducts of the salivary glands.
the long ducts of the membranous labyrinth of the ear.
the excretory ducts of the sublingual salivary glands.
the duct that drains the submandibular gland and opens at the sublingual caruncle. Called also submaxillary duct.
submandibular duct (above).
a duct beginning in the cisterna chyli and emptying into the venous system at the junction of the left subclavian and left jugular veins. It acts as a channel for the collection of lymph from the portions of the body caudal to the diaphragm and from the left side of the body cranial to the diaphragm.
the transient, non-patent duct, from the thyroid gland to the floor of the pharynx which is the legacy of the development of the thyroid from the floor of the pharynx.
see meckel's diverticulum.
emanating from or pertaining to the mesonephros.
embryonal structure that develops into the vas deferens and epididymis in males and remains vestigial in females. Called also wolffian duct. It is subject to a variety of manifestations of segmental aplasia and hypoplasia, especially in bulls. In mares remnants of the ducts may become cystic and produce paraovarian cyst.
excretory tube of the mesonephros; becomes the mesonephric duct and contributes in the adult to the vasa efferentia of the male.
embryonic tubules which connect at one end with a blood vessel, at the other with the mesonephric duct.