rudder: [OE] Rudder comes from the same source as English row ‘use oars’ – prehistoric Germanic *rō- ‘steer’. Indeed it originally denoted an ‘oar used for steering’; the modern application to a fixed steering surface did not emerge until the 14th century. Its west Germanic ancestor *rōthra- also produced German ruder and Dutch roer. => row
rudder (n.)
mid-15c. alteration of Middle English rother, from Old English roeor "paddle, oar," from Proto-Germanic *rothru- (cognates: Old Frisian roeer, Middle Low German roder, Middle Dutch roeder, Dutch roer, Old High German ruodar, German Ruder "oar"), from *ro- "steer" (see row (v.)) + suffix -tra, used to form neutral names of tools.
Meaning "broad, flat piece of wood attached to the stern of a boat and guided by a tiller for use in steering" is from c. 1300. For shift of -th- to -d- compare burden (n.1), murder (n.); simultaneous but opposite to the movement that turned -d- to -th- in father (n.), etc.
例文
1. It was not yet clear how the rudder had sheared off.
船舵がどのように切断されたのかは不明である。
2.Turn the rudder slightly so that we can ease the boat round.
ゆっくり舵を取ることで、船を穏やかに曲げることができます。
3.An oar often acts as rudder .
パドルは舵の役割を果たすことが多い。
4.There is no rudder as such，so the craft can be stered only when under power.
には真の方向舵がないので、動力駆動の場合にのみ船を操ることができる。
5.A sailor uses the rudder to make the ship go in the correct direction.