Steerage is the act of steering a ship.
Steerage and steerage way
The rudder of a vessel can steer the ship only when water is passing over it. Hence, when a ship is not moving relative to the water it is in or cannot move its rudder, it does not respond to the helm and is said to have "lost steerage." The motion of a ship through the water is known as "making way." When a vessel is moving fast enough through the water that it turns in response to the helm, it is said to have "steerage way." That is why boats on rivers must always be under propulsion, even when traveling downstream.