noun, plural os·ti·a [os-tee-uh] /ˈɒs ti ə/.
Origin of ostium
Examples from the Web for ostium
Historical Examples of ostium
Here in the door-way, or ostium, we stop to note the "Salve!"Historic Boys
Elbridge Streeter Brooks
The porter, who sat in a niche of the entrance-corridor (ostium).Quintus Claudius, Volume 1 of 2
This will bring the anterior wall of the sinus with its ostium into view.
Double doors admitted the visitor to the entrance-hall, or ostium.Stories of the Olden Time
With the help of cocaine the ostium can then be enlarged with various instruments.