Where Is the Monstrance Kept?

In many of them, during Eucharistic adoration, the celebrant displays the sacrament in the monstrance, typically on the altar. When not being displayed, the reserved sacrament is locked in a tabernacle (more common in Roman Catholicism) or aumbry (more common in the other traditions mentioned).

Where is the consecrated host kept?

Communion for the sick - Catholic Rite

All consecrated hosts are kept in the ciborium inside the Tabernacle. When bringing Communion to the homebound or sick, a small to medium-sized receptacle called a pyx is used by lay ministers, deacons and priests.

What is the host placed in for adoration?

A monstrance is the vessel used to display the consecrated Eucharistic Host, during Eucharistic adoration or benediction.