Winged altarpiece

A winged altarpiece (also "folding altar") or winged retable is a special form of altarpiece (reredos, occasionally retable), common in Central Europe, in which the fixed shrine or "corpus" can be enclosed by two (triptych), four (pentaptych) or more (polyptych) movable wings. The technical terms are derived from : "trís" or "triple"; πέντε: "pénte" or "five"; πολύς: "polýs" or "many"; and πτυχή: "ptychē" or "fold, layer".
Because the winged altar can display different scenes on weekdays, Sundays or holidays, based on the motifs and type of decoration (painted panels or reliefs), it is also called a liturgical altar.
An altarpiece is often mounted on the altar shrine, but more usually it has a carving (carved altar). Above the retable may be found the crowning or superstructure, pinnacles and flowers of the cross. Relics can be housed below it, in a reliquary in the predella lying on the altar stone.