A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other conveyance that moves through a fluid medium. On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane.

What is the word rudder mean?

1 : an underwater blade that is positioned at the stern of a boat or ship and controlled by its helm and that when turned causes the vessel's head to turn in the same direction.

What does rudder mean on a boat?

rudder, part of the steering apparatus of a boat or ship that is fastened outside the hull, usually at the stern. The most common form consists of a nearly flat, smooth surface of wood or metal hinged at its forward edge to the sternpost. It operates on the principle of unequal water pressures.