Altar – Ciborium
The more familiar term baldachin and the ancient term ciborium refer to the structure over the altar. The ritual involves placing gifts of bread and wine on the altar and invoking the Holy Spirit upon them so that all who share in this meal may be one. The offering and invocation are expressed architecturally by the cubic altar and arching ciborium. Traditionally ciboria have an image of the Spirit in the form of a dove on the ceiling at its highest point, brooding over the gifts placed on the altar below. This is a new composition at the Duomo or Cathedral of St Lawrence, Trapani, Sicily
Cathedral of San Lorenzo, Trapani, Scicily (external link)