The Corporal. From the Latin word corpus” meaning body. The corporal is a square white starched linen cloth. At the beginning of the Liturgy of the Eucharist it is spread on the altar (GIRM no. 73). It functions like a placemat upon which the chalice and paten and also the ciborium containing the smaller hosts “are placed on the altar by the priest to the accompaniment of the prescribed formulas” . (GIRM no.75)
In the ancient Roman Sacramentaries (Liturgical Books) it was also called shroud referring to the burial cloth of Jesus.