Ŏs'ti-a-ry, n.

(Synop., § 130), n. [From Lat. ostium, door, entrance, the mouth of a river, from os, mouth.]

1. (Geog.) The mouth or opening by which a river discharges its waters into the sea, or into a lake; an estuary. [Rare.] Browne.
2. One who keeps the door, especially the door of a church; a porter. [Obs.]

Lastly, ostiaries, which used to ring the bells and open and shut the church doors. N. Bacon.