monstrance

A receptacle in which the host is held and displayed.

In the Roman Catholic Church, originally, any receptacle in which sacred relics were held up to view; after the fourteenth century, restricted to the transparent or glass-faced shrine in which the consecrated host is presented for the adoration of the people, either while being carried in procession or when exposed on the altar.

A transparent pyx, in which the consecrated host is exposed to view.

An ornamental, often precious receptacle, either open or with a transparent cover, in which the consecrated host is placed for veneration.

proof by a process of argument or a series of proposition proving an asserted conclusion

(Roman Catholic Church) a vessel (usually of gold or silver) in which the consecrated Host is exposed for adoration