Latin ōstiumdoor, openingfromōsmouthōs- in Indo-European roots
American Heritage Dictionary of the English Language, 5th Edition
Ostium Sentence Examples
Two or three membranous flaps, held by numerous chordae tendineae, form a true mitral valve, and allow the blood to pass through the left ostium atrioventriculare.
The small opening among the fimbriae by which the tube communicates with the peritoneal cavity is known as the ostium abdominale, and from this the lumen of the tube runs from four to four and a half inches, until it opens into the cavity of the uterus by an extremely small opening.
i), and becomes perforated in the same way at its outer side by a "septal ostium," forming as it were the rudiment of a ring-canal.
Aglossa, - Eustachian tubes united into a single ostium pharyngeum; no tongue.
It was the first colony ever founded by Rome - according to the Romans themselves, by Ancus Martius - and took its name from its position at the mouth (ostium) of the river.