(Old French: porte, “door” + coleice, “sliding”). In medieval fortifications a vertically closing gate, usually in the form of a grating made of wood, metal, or both. The portcullis slides down through grooves in the jambs of the gateway. It could be lowered or raised rapidly using chains or ropes operated by a winch.

Portcullis, Stirling Castle, Scotland. Photo: David Monniaux.