rud·der
noun/ˈrʌdə(r)/
/ˈrʌdər/
- a piece of wood or metal at the back of a boat or an aircraft that is used for controlling its direction
enlarge image（船的）舵；（飞机的）方向舵 Word OriginOld English rōther ‘paddle, oar’, of West Germanic origin; related to Dutch roer, German Ruder, also to the verb row1.