duke
noun /djuːk/
  /duːk/
 - a nobleman of the highest rank公爵 - the Duke of Edinburgh爱丁堡公爵 
 
- the Duke of Edinburgh
- (in some parts of Europe, especially in the past) a male leader of a small independent state(尤指旧时欧洲部分地区小公国的)君主 see also archduke, duchess, duchy, grand duke
词源Old English (denoting the ruler of a duchy), from Old French duc, from Latin dux, duc- ‘leader’; related to ducere ‘to lead’.