Old English rōþor (“rudder”), from Proto-Germanic *rōþrą (“rudder"; literally, "paddle, instrument for rowing”), from Proto-Germanic *rōaną "to row" from Proto-Indo-European *ere-, *rē- (“to row”) + Proto-Germanic *-þrą, *-þraz, instrumental suffix. Akin to Old English rōwan (“to row”). More at rōwan, -þor.
rudder (plural rudders)
- (nautical) An underwater vane used to steer a vessel. The rudder is controlled by means of a wheel, tiller or other apparatus (modern vessels can be controlled even with a joystick or an autopilot).
- (aeronautics) A control surface on the vertical stabilizer of a fixed-wing aircraft or an autogyro. On some craft, the entire vertical stabilizer comprises the rudder. The rudder is controlled by foot-operated control pedals.
- A riddle or sieve.