What is (a) (Rom. Antiq.) An unroofed space consecrated to a divinity. (b) (Eccl.) A small monumental chapel in a church. Shipley called?

sacellum — (a) (Rom. Antiq.) An unroofed space consecrated to a divinity. (b) (Eccl.) A small monumental chapel in a church. Shipley. (Webster's 1913.)

Sources