sedile (pl. sedilia). Seat. The plural term is used to describe the series of stone seats (usually three) in a church set in the south wall of the chancel, often crowned with elaborate canopies and pinnacles, used by officiating clergy. Sedilia, collectively known as the prismatory, may include the piscina within a series of arched niches.
"sedile." A Dictionary of Architecture and Landscape Architecture. . Encyclopedia.com. 22 Apr. 2019 <https://www.encyclopedia.com>.