- A gap in or entrance to an organ, tube, or cavity. SEE ALSO: aperture, fossa, ostium, orifice, pore.- o. of aqueduct of midbrain [TA] entrance to the cerebral aqueduct; point at which the caudal part of the third ventricle is continuous with the cerebral aqueduct of the midbrain; located on the midline immediately ventral to the posterior commissure. SYN: apertura aqueductus mesencephali [TA], apertura aqueductus cerebri, o. of cerebral aqueduct, aditus ad aqueductum cerebri, Bartholin anus.- cardiac o. SYN: cardial orifice.- openings of carotid canal [TA] the o. at each extremity of the carotid canal in the pyramidal petrous part of the temporal bone; the external o. of the carotid canal is on the inferior surface of the pyramid; the internal o. of the canal is at the apex of the petrous part. SYN: carotid foramen.- caval o. of diaphragm [TA] an o. in the right lobe of the central tendon of the diaphragm that transmits the inferior vena cava and branches of the right phrenic nerve. SYN: foramen of vena cava, foramen quadratum, foramen venae cavae, vena caval foramen.- o. of coronary sinus [TA] orifice by which the coronary sinus enters and drains into the right atrium of the heart. SYN: ostium sinus coronarii [TA].- external o. of cochlear canaliculus [TA] the external o. of the cochlear aqueduct on the temporal bone medial to the jugular fossa. SYN: apertura canaliculi cochleae, external aperture of cochlear canaliculus.- o. of frontal sinus [TA] one of a pair of openings in the floor of the frontal sinuses in the nasal part of the frontal bone, through which the frontal sinuses communicate with the ethmoidal infundibulum via the frontonasal duct. SYN: apertura sinus frontalis [TA], frontal sinus aperture.- o. of inferior vena cava [TA] the orifice through which the inferior vena cava opens into the right atrium. SYN: ostium venae cavae inferioris [TA], orifice of inferior vena cava.- orbital o. [TA] the somewhat quadrangular anterior entrance to the orbit that forms the base of the pyramid-shaped orbital cavity. It is bounded by the sharp supra-, infra-, and lateral orbital margins and a less obvious medial margin on each side of the upper nose. SYN: aditus orbitae [TA], aperture of orbit.- openings of papillary ducts [TA] numerous minute openings, the apertures of the papillary ducts converging on the apical pole of each renal papilla. SYN: foramina papillaria renis [TA], papillary foramina of kidney.- pharyngeal o. of pharyngotympanic (auditory) tube [TA] an o. in the upper part of the nasopharynx about 1.2 cm behind the posterior extremity of the inferior concha on each side. SYN: ostium pharyngeum tubae auditivae [TA], ostium pharyngeum tubae auditoriae, pharyngeal o. of eustachian tube.- o. of pulmonary trunk [TA] the o. of the pulmonary trunk from the right ventricle, guarded by the pulmonary valve. SYN: ostium trunci pulmonalis [TA], pulmonary orifice.- openings of pulmonary veins [TA] the orifices of the pulmonary veins, usually two on each side, in the wall of the left atrium. SYN: ostia venarum pulmonalium [TA].- saphenous o. [TA] the o. in the fascia lata inferior to the medial part of the inguinal ligament through which the saphenous vein passes to enter the femoral vein. SYN: hiatus saphenus [TA], fossa ovalis (2), saphenous hiatus.- openings of smallest cardiac veins [TA] a number of fossae in the wall of the right atrium, containing the openings of minute intramural veins. SYN: foramina of the smallest veins of heart, foramina of the venae minimae, foramina venarum minimarum cordis, Lannelongue foramina, thebesian foramina, Vieussens foramina.- o. of the sphenoidal sinus [TA] one of the pair of openings in the body of the sphenoid bone through which the sphenoid sinuses communicate with the sphenoethmoidal recess of the nasal cavity. SYN: apertura sinus sphenoidalis [TA], sphenoidal sinus aperture.- o. of superior vena cava [TA] the point of entry of the superior vena cava into the right atrium. SYN: ostium venae cavae superioris [TA], orifice of superior vena cava.- tympanic o. of canaliculus for chorda tympani SYN: tympanic aperture of canaliculus for chorda tympani.- tympanic o. of pharyngotympanic (auditory) tube [TA] an o. in the anterior part of the tympanic cavity below the canal for the tensor tympani (muscle). SYN: ostium tympanicum tubae auditivae [TA], tympanic o. of eustachian tube.- o. of vestibular canaliculus [TA] the external o. of the vestibular aqueduct on the posterior surface of the petrous part of the temporal bone near the groove for the sigmoid sinus. SYN: apertura canaliculi vestibuli, external aperture of vestibular aqueduct.
* * *open·ing 'ōp-(ə-)niŋ n1) an act or instance of making or becoming open2) something (as an anatomical aperture) that is open or opens
* * *open·ing (oґpən-ing) an aperture, orifice, or open space; see also inlet and outlet. Anatomic nomenclature for various types of openings includes aditus, apertura, foramen, fossa, hiatus, and ostium.
Medical dictionary. 2011.
Look at other dictionaries:
Opening — may refer to: Games Chess opening Backgammon opening theory Opening bid, a term from contract bridge Other Grand opening of a business or other institution Al Fatiha, The Opening , first chapter of the Qur an Opening, a morphological filtering… … Wikipedia
Opening — O pen*ing, n. 1. The act or process of opening; a beginning; commencement; first appearance; as, the opening of a speech. [1913 Webster] The opening of your glory was like that of light. Dryden. [1913 Webster] 2. A place which is open; a breach;… … The Collaborative International Dictionary of English
Opening — steht für: Grand Opening, (Große Eröffnung), offizielle Eröffnung für den Kundenbetrieb Soft Opening (Sanfte Eröffnung), inoffizielle Eröffnung für den Kundenbetrieb Opening (Bildverarbeitung), morphologische Basis Operation in der digitalen… … Deutsch Wikipedia
opening up — n the opening up of sth when something is made less restricted and more available to people ▪ the opening up of opportunities for women ▪ the opening up of new areas to cultivation … Dictionary of contemporary English
opening-up — UK US noun [S] COMMERCE ► OPENING(Cf. ↑opening) noun … Financial and business terms
opening — (n.) O.E. openung act of opening (a door, mouth, etc.), disclosure, manifestation, verbal noun from prp. of OPEN (Cf. open) (v.). Meaning vacant space, hole, aperture, doorway is attested from c.1200. Meaning act of opening (a place, to the… … Etymology dictionary
opening — [n1] gap, hole aperture, breach, break, cavity, chink, cleft, crack, cranny, crevice, cut, discontinuity, door, fissure, hatch, interstice, mouth, orifice, outlet, perforation, recess, rent, rift, rupture, scuttle, slit, slot, space, split, spout … New thesaurus
opening — [ō′pə niŋ΄, ōp′niŋ΄] n. [ME openyng] 1. a becoming open or causing to be open 2. an open place or part; hole; gap; aperture ☆ 3. a clearing in the midst of a wooded area 4. a) a beginning; first part; commencement b) start … English World dictionary
opening — index access (right of way), admission (entry), admittance (means of approach), chance (fortuity) … Law dictionary
opening — ► NOUN 1) an aperture or gap. 2) a beginning; an initial part. 3) a ceremony at which a building, show, etc. is declared to be open. 4) an opportunity to achieve something. 5) an available job or position. ► ADJECTIVE ▪ coming at the beginning;… … English terms dictionary
opening — The period at the beginning of the trading session officially designated by an exchange, during which all transactions are considered made at the opening. Related: close. Bloomberg Financial Dictionary The period at the beginning of the trading… … Financial and business terms