ostium

noun

os·​ti·​um ˈä-stē-əm How to pronounce ostium (audio)
plural ostia ˈä-stē-ə How to pronounce ostium (audio)
: a mouthlike opening in a bodily part (such as a fallopian tube or a blood vessel)

Examples of ostium in a Sentence

Recent Examples on the Web Surgical treatment of a fungus ball consists in opening the infected sinus cavity at the level of its ostium and removing fungal concretions while sparing the normal mucosa. Seriously Science, Discover Magazine, 9 Jan. 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ostium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Latin, door, mouth of a river; akin to Latin os mouth — more at oral

First Known Use

1683, in the meaning defined above

Time Traveler
The first known use of ostium was in 1683

Dictionary Entries Near ostium

Cite this Entry

“Ostium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ostium. Accessed 26 Apr. 2024.

Medical Definition

ostium

noun
os·​ti·​um ˈäs-tē-əm How to pronounce ostium (audio)
plural ostia -tē-ə How to pronounce ostium (audio)
: a mouthlike opening in a bodily part (as a fallopian tube or a blood vessel)
stenosis of coronary ostiaR. L. Cecil & R. F. Loeb

More from Merriam-Webster on ostium

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