I. ˈrədə(r) noun
( -s )
Usage: often attributive
Etymology: Middle English rother, from Old English rōther paddle; akin to Old High German ruodar rudder, Old Norse rōthr act of steering; derivative from the root of English row (I)
1.
a. : a flat piece or structure of wood or metal attached upright to the sternpost or in single-screw ships to the rudderpost by hinges or by pintles and gudgeons so that it can be turned (as by a tiller) causing the ship's head to turn in the same direction because of the resistance offered to the water by the rudder
b. : a hinged or movable auxiliary airfoil usually attached at the rear end that serves to control direction of flight in the horizontal plane by impressing yawing moments on an airplane
2. : rudder angle
what rudder , if any, the ship is carrying — Manual of Seamanship
3. : one that resembles a rudder in being a guide or governor
for rhyme the rudder is of verses — Samuel Butler †1680
4. : a plate or wheel at the rear end of a lister to guide and steady the moldboards and assist in bearing the weight
5. : a tail especially of an otter
6. : a swinging support for the leaf of a drop-leaf table
II. transitive verb
( -ed/-ing/-s )
1. : steer
2. : to provide with a rudder