ostium

noun os·ti·um \ˈäs-tē-əm\

plural os·tia \-tē-ə\

Definition of OSTIUM

: a mouthlike opening in a bodily part (as a fallopian tube or a blood vessel)

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

First Known Use: 1828

Medical Dictionary

noun os·ti·um \ˈäs-tē-əm\

plural os·tia \-tē-ə\

: a mouthlike opening in a bodily part (as a fallopian tube or a blood vessel) <stenosis of coronary ostia—R. L. Cecil & R. F. Loeb>

Next Word in the Dictionary: ostlerPrevious Word in the Dictionary: ostioleAll Words Near: ostium

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