- Anatomy, Zoology. a small opening or orifice, as at the end of the oviduct.
- Zoology. one of the tiny holes in the body of a sponge.
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.
- any of the pores in sponges through which water enters the body
- any of the openings in the heart of an arthropod through which blood enters
- any similar opening
Word Origin for ostium
- A small opening or orifice, as in a body organ.