/os"tee er'ee/ , n. , pl. ostiaries .
1. Also called doorkeeper, porter . Rom. Cath. Ch.
a. a member of the lowest-ranking of the four minor orders.
b. the order itself. Cf. acolyte (def. 2), exorcist (def. 2), lector (def. 2).
2. a doorkeeper, as of a church.
[ 1400-50; late ME hostiary ostiarius doorkeeper, equiv. to osti ( um ) door, entrance (see OSTIUM) + -arius -ARY ]