grating
n. countablen. a wooden or metal frame made of bars that cross each other. On a ship, it lets air and light into the lower levels while giving people a surface to walk on.
n. a framework of parallel or crossed bars used to cover an opening, especially on a ship's deck to provide ventilation and light to the lower decks.
The sailor stepped carefully over the wooden grating on the deck.
Fresh air circulated through the open grating, cooling the cramped quarters below the main deck during the tropical voyage.
Traditional naval architecture utilized heavy oak gratings to ensure that even when the hatches were secured against high seas, the hold remained ventilated to prevent the accumulation of dampness and rot.
From grat(e) + -ing.
Often used in the plural when referring to the entire set of covers on a vessel.