n.1.  Any of various heavy motor vehicles designed for carrying or pulling loads.
2.  A hand truck.
3. a.  A wheeled platform, sometimes equipped with a motor, for conveying loads in a warehouse or freight yard.
b.  A set of bookshelves mounted on four wheels or casters, used in libraries.
 4. a.  One of the swiveling frames of wheels under each end of a railroad car or trolley car.
b.  Either of the frames housing a pair of wheels on a skateboard or landboard.
 5.  Nautical   A small piece of wood placed at the top of a mast or flagpole, usually having holes through which halyards can be passed.
6.  Chiefly British   A railroad freight car without a top.