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.
2.
any open platform suggesting an exposed deck of a ship.
3.
an open, unroofed porch or platform extending from a house or other building.
Compare sun deck.
4.
any level, tier, or vertical section, as of a structure or machine.
5.
flight deck (def 2).
6.
a flat or nearly flat watertight surface, as at the top of a French roof.
7.
a floor or roof surface composed of decking units.