ostium

American  

[os-tee-uhm] / ˈɒs ti əm /

noun

• ostia
  plural

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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Other Word Forms

Noun Inflected Forms

• ostia
  plural

Etymology

Origin of ostium

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

Example Sentences

See Examples For:

ostium ostia

When the inflammation is adjacent to the ostium it leads to the matting together of the tubal fimbriae and glues them to an adjacent organ.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" by Various

Here in the door-way, or ostium, we stop to note the "Salve!"

From Historic Boys Their Endeavours, Their Achievements, and Their Times by Elbridge Streeter Brooks

Double doors admitted the visitor to the entrance-hall or ostium.

From The Story of Rome from the Earliest Times to the End of the Republic by Arthur Gilman

A young and sturdy "janitor" opened the door leading to the ostium, over which a magpie confined in a cage greeted them noisily with the word, "Salve!"

From Quo Vadis: a narrative of the time of Nero by Jeremiah Curtin

A probe is then passed into the ostium, and the anterior wall of the sinus is removed with a curette or rongeur forceps.

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

The sponge coats unwanted detritus and waste with mucus and sends the coated particles out through small pores in its body called ostia.

From Science Magazine ● Aug. 10, 2022

Those “little mouths” are called ostia, and the openings where water flows out are oscula.

From New York Times ● Aug. 10, 2022

Other scientists had observed sponges sneezing by pushing water through their ostia before, but no one had confirmed the behavior was a mode of self-cleaning until now.

From Science Magazine ● Aug. 10, 2022

Porocytes, hollow tube-shaped cells that span the body of the sponge, regulate movement of water through the ostia.

From Textbooks ● Jan. 1, 2015

Bishop Leslie transfers this same fight to the banks of the Annan in Dumfriesshire, describing it as having occurred during an invasion of Cumbria, "ad Annandiæ amnis ostia."

From Archaeological Essays, Vol. 1 by John Stuart