ostium

American  

[os-tee-uhm] / ˈɒs ti əm /

noun

plural

ostia

1. Anatomy, Zoology. a small opening or orifice, as at the end of the oviduct.

2. Zoology. one of the tiny holes in the body of a sponge.

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ostium British  

/ ˈɒstɪəm /

noun

1. any of the pores in sponges through which water enters the body

2. any of the openings in the heart of an arthropod through which blood enters

3. any similar opening

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Etymology

Origin of ostium

First recorded in 1655–65, ostium is from the Latin word ōstium entrance, river mouth

Example Sentences

The removal of the middle turbinated bone permits of inspection of the ostium sphenoidale by anterior rhinoscopy, and pus may be seen escaping from the orifice.

From Manual of Surgery Volume Second: Extremities—Head—Neck. Sixth Edition. by Miles, Alexander

At first it does not quite reach the endocardial cushions in the auricular canal, already mentioned, but leaves a gap, called the ostium primum, between.

From Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 2 "Hearing" to "Helmond" by Various

Decimo quarto Kalendas Januarii Patagonicis recognitis litoribus ad ostium appulit freti.

From Narrative of the surveying voyages of His Majesty's ships Adventure and Beagle, between the years 1826 and 1836 Volume I. - Proceedings of the First Expedition, 1826-1830 by Fitzroy, Robert

The porch of the ostium was supported by four columns delicately fluted and painted, the lower half in dull crimson, the upper in ochre.

From The Lion's Brood by Osborne, Duffield

Primis enim duabus noctibus, cum chori psallentium corpori assistabant, advenientes Dæmones ostium ecclesiæ confregerunt ingenti obice clausum, extremasque cathenas negotio levi dirumpunt: media autem quæ fortior erat, illibata manebat.

From Poems, 1799 by Southey, Robert