a square or oblong opening in the deck of a ship, affording a passage into the hold, or from one deck to another. Hatchway is also applied to the passage through a falling door in the top of a house. In ships, the main-hatchway is placed before the mainmast, and is the largest in the ship; the fore-hatchway is a little abaft the foremast, or at the break of the forecastle; and the after-hatchway between the mainmast and the mizen.