Nautical. a floorlike surface wholly or partially occupying one level of a hull, superstructure, or deckhouse, generally cambered, and often serving as a member for strengthening the structure of a vessel. the space between such a surface and the next such surface above: Our stateroom was on B deck.
any open platform suggesting an exposed deck of a ship.
an open, unroofed porch or platform extending from a house or other building. Compare sun deck.
any level, tier, or vertical section, as of a structure or machine.