Also spelled Zion.
The largest of the two hills to the southwest of Jerusalem, on which the city of David was built, and which became the center of Jewish life and worship.
Used to mean house or household of God, it connotes variously the Israelites and their religious system, the Christian Church, heaven as the final home of believers, a place of worship or meeting-house.
It is of special interest as the site of the Cenacle, the first meeting-place of Christians, the scene of the Last Supper and of the Descent of the Holy Ghost.
New Catholic Dictionary