/pawrt kul"is, pohrt-/ , n.
(esp. in medieval castles) a strong grating, as of iron, made to slide along vertical grooves at the sides of a gateway of a fortified place and let down to prevent passage.
[ 1300-50; ME portecolys porte coleice, equiv. to porte PORT 4 + coleice, fem. of coleis flowing, sliding colaticius; see COULEE, -ITIOUS ]