polyptych

polyptych. A picture or other work of art made up of four or more linked parts (usually wooden panels). It was a popular form for altarpieces from the 14th century to the early 16th century. Italian polyptychs of this time typically include a predella beneath the main panel or tier, the whole enclosed in an elaborate frame. In northern Europe, polyptychs often had panels hinged together and painted on both sides, so that they could be folded to create different pictorial compositions (sometimes ones that were appropriate for particular liturgical seasons or events). Jan van Eyck's Ghent Altarpiece and Grünewald's Isenheim Altarpiece are among the famous examples of this type. See also diptych and triptych.