hiatus

hiatus /hi·a·tus/ (hi-a´tus) [L.] an opening, gap, or cleft.hia´tal

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aortic hiatus  the opening in the diaphragm through which the aorta and thoracic duct pass.

Inferior view of the diaphragm, showing the openings through which the aorta, esophagus, and vena cava pass.

esophageal hiatus  the opening in the diaphragm for the passage of the esophagus and the vagus nerves.

pleuroperitoneal hiatus  foramen of Bochdalek; a posterolateral opening in the fetal diaphragm; its failure to close leaves a congenital posterolateral defect that may become a site for congenital diaphragmatic hernia.

saphenous hiatus  the depression in the fascia lata bridged by the cribriform fascia and perforated by the great saphenous vein.

semilunar hiatus  the groove in the ethmoid bone through which the anterior ethmoidal air cells, the maxillary sinus, and sometimes the frontonasal duct drain via the ethmoid infundibulum.

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hi·a·tus (h-ts)

n. pl. hiatus or hi·a·tus·es

1. An aperture or fissure in an organ or a body part.

2. A foramen.

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hi·atal adj.

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hiatus

[hī·ā′təs]

Etymology: L, hiare, to stand open

a usually normal opening in a membrane or other body structure. hiatal, adj.

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hiatus

pl. hiatus [L.] an aperture, gap, cleft or opening.

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aortic hiatus, hiatus aorticus

the opening in the diaphragm through which the aorta and thoracic duct pass.

esophageal hiatus hernia

see hiatal hernia.

esophageal hiatus, hiatus esophageus

the opening in the diaphragm for the passage of the esophagus and the vagus nerves.

vena caval hiatus

the opening in the diaphragm for the passage of the caudal vena cava; properly called foramen venae cavae.