Triptych is a painting or relief composed of three panels, often hinged so the side wings can fold over the central image.
A triptych is an artwork composed of three panels, typically with a larger central panel flanked by two narrower wings of equal size. The format originated in late antiquity for portable devotional objects and became the dominant altarpiece form in late-medieval and early Renaissance Northern Europe. Hinged triptychs could be closed during the liturgical week and opened on feast days, presenting a painted exterior in subdued grisaille and a brilliant interior of polychrome scenes. Among the masterpieces of the form: the Mérode Altarpiece by Robert Campin (c. 1427–1432, Cloisters Museum, New York), the Portinari Altarpiece by Hugo van der Goes (1475–1476, Uffizi), the Ghent Altarpiece by Jan van Eyck (1432, properly a polyptych), and Hieronymus Bosch's 'The Garden of Earthly Delights' (c. 1490–1510, Prado), whose three panels depict Paradise, the contemporary world, and Hell with hallucinatory invention. The triptych form survived into modernity in works by Max Beckmann, Otto Dix (his 'Trench' triptych of 1929–1932), and Francis Bacon, whose 'Three Studies for Figures at the Base of a Crucifixion' (1944) brought the medieval altarpiece form into post-war existential painting.