A chief pall-bearer or the principal cloth covering used at a funeral; the supreme funeral pallium.
From arch- (meaning 'chief') plus pall (from Latin pallium, 'cloth' or 'cloak'). A pall is the cloth covering a coffin, and the archpall would be the most important or ornate version.
Medieval funerals had strict hierarchies even among people carrying the coffin—the archpall-bearer was like the head usher, a position of honor for distinguished mourners who got special robes and walked closest to the deceased.
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