ostium


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Related to ostium: Ostium primum, Ostium secundum

ostium

 [os´te-um] (L.)
an opening or orifice. adj., adj os´tial.
ostium abdomina´le the fimbriated end of the fallopian tube.
ostium cardi´acum the orifice between the esophagus and the stomach.
coronary ostium either of the two openings in the aortic sinuses that mark the origins of the left and right coronary arteries.
ostium inter´num ostium uterinum tubae.
ostium pharyn´geum the nasopharyngeal end of the eustachian tube.
ostium pri´mum an opening in the lower portion of the membrane dividing the embryonic heart into right and left sides. See also atrial septal defect and congenital heart defect.
ostium secun´dum an opening in the upper portion of the membrane dividing the embryonic heart into right and left sides, appearing later than the ostium primum. See also atrial septal defect and congenital heart defect.)
tympanic ostium (ostium tympa´nicum) the opening of the eustachian tube on the carotid wall of the tympanic cavity.
ostium u´teri the external opening of the cervix of the uterus into the vagina.
ostium uteri´num tu´bae the uterine end of the fallopian tube; the point where the cavity of the tube becomes continuous with that of the uterus.
ostium vagi´nae the external orifice of the vagina.

os·ti·um

, pl.

os·ti·a

(os'tē-ŭm, -ă), [TA]
A small opening, especially one of entrance into a hollow organ or canal.
See also: orifice, opening, os, mouth (2).
[L. door, entrance, mouth]

ostium

/os·ti·um/ (os´te-um) pl. os´tia   [L.] an opening or orifice.os´tial
ostium abdomina´le tu´bae uteri´nae  the funnel-shaped opening where the uterine tube meets the abdominal cavity.
coronary ostium  either of the two openings in the aortic sinus that mark the origin of the (left and right) coronary arteries.
ostium inter´num u´teri  o. uterinum tubae uterinae.
ostium pharyn´geum tu´bae auditi´vae  the pharyngeal opening of the auditory tube.
ostium pri´mum  an opening in the lower portion of the membrane dividing the embryonic heart into right and left sides.
ostium secun´dum  an opening high in the septum of the embryonic heart, approximately where the foramen ovale will later appear.
tympanic ostium , ostium tympa´nicum tu´bae auditi´vae the opening of the auditory tube on the carotid wall of the tympanic cavity.
ostium u´teri  the external opening of the uterine cervix into the vagina.
ostium uteri´num tu´bae uteri´nae  the point where the cavity of the uterine tube becomes continuous with that of the uterus.
ostium vagi´nae  the external orifice of the vagina.

ostium

(ŏs′tē-əm)
n. pl. os·tia (-tē-ə)
A small opening or orifice, as in a body organ or passage.

ostium

See orifice.

ostium

Plural, ostia Medtalk An opening, aperture

os·ti·um

, pl. ostia (os'tē-ŭm, -ă) [TA]
A small opening, especially one that enters into a hollow organ or canal.
[L. door, entrance, mouth]

ostium

An opening or mouth.

ostium

any of numerous openings present in sponges through which water is drawn in.

ostium (ˑ·stē·m),

n an opening or passage.

os·ti·um

, pl. ostia (os'tē-ŭm, -ă) [TA]
Small opening, especially one of entrance into a hollow organ or canal.
See also: orifice, mouth (2)
[L. door, entrance, mouth]

ostium

pl. ostia [L.] a mouth or orifice; a general term to designate an opening into a tubular organ, or between two distinct body cavities. The names of most ostia are self-defining.

ostium abdominale
the fimbriated end of the uterine tube.
ostium cardiacum
the opening of the esophagus into the stomach.
coronary ostium
either of the two openings in the aortic sinuses which mark the origin of the (left and right) coronary arteries.
ostium ejaculatorium
the common orifice of the ductus deferens and the excretory duct of the seminal vesicle into the urethra.
ostium internum
ostium uterinum tubae.
ostium pharyngeum
the nasopharyngeal end of the auditory tube.
ostium primum
an opening in the lower portion of the membrane dividing the embryonic atria into right and left sides. Called also foramen primum. See also atrial septal defect.
ostium pulmonary vein
the opening of the pulmonary vein into the left atrium.
ostium ruminoreticulare
the opening between the rumen and the reticulum.
ostium secundum
an opening in the upper portion of the membrane dividing the embryonic atria into right and left sides, appearing later than the ostium primum. Called also foramen secundum. See also atrial septal defect.
tympanic ostium, ostium tympanicum
the opening of the auditory tube on the carotid wall of the tympanic cavity.
ostium uteri
the external opening of the cervix of the uterus into the vagina.
ostium uterinum tubae
the point where the cavity of the uterine tube becomes continuous with that of the uterus.
ostium vaginae
the external orifice of the vagina.
References in periodicals archive ?
Opening of the ethmoid bulla in this area with a microdebrider confirmed that this was a true ostium of the left ethmoid bulla.
the ostium opening and dependent positions in the nasal cavity, choana, and nasopharynx).
No further surgical manipulation was done in the sphenoid sinus, but the sphenoid ostium was carefully enlarged.
1) The ostium of the ethmoid bulla is usually found in the posterior and medial aspect of the bulla draining into the hiatus semilunaris superior; sometimes it is found in the anterior or lateral ethmoid bulla wall, the ethmoid infundibulum, the retrobullar recess, or the hiatus semilunaris inferior.
The Sideguard's trumpet-shaped design helps the stent conform to the ostium, allowing for complete stent-to-wall apposition and continuous drug delivery.
Coronal computed tomography (CT) detected a foreign body in the right maxillary sinus ostium (figure).
In his revisional study on the genus Ditrigona, Wilkinson (1968) enumerated the generic characters as follow: antennal form variable, serrate, unipectinate or bipectinate; thorax and abdomen usually white; forewing not strongly falcate; the fasciae gray to brown; uncus present either bifid, bifurcate or single; valves variably developed; aedeagus strongly developed and variously shaped; ostium variable; corpus bursae in most species with signum and with an accessory sac.
The above abnormality was accompanied by an ostium secundum-type atrial septal defect.
The end point may be subtle, but continuous movement from one ostium to the other with the hysteroscope, and a uniform appearance of the uterine fundus, should be achieved.
In this rare anomaly only one coronary artery arises from a single ostium (0.