| ostia | Plural of ostium. Origin: L. (05 Mar 2000) |
|---|---|
| ostia venarum pulmonalium | The orifices of the pulmonary veins, usually two on each side, in the wall of the left atrium. Synonym: ostia venarum pulmonalium. (05 Mar 2000) |
| ostial | Relating to any orifice, or ostium. (05 Mar 2000) |
| ostial sphincter | A thickening of circular muscular fibres at the level of an orifice. (05 Mar 2000) |