hood  
noun [ C ] uk/hʊd/ us/hʊd/
  (CLOTHING)         
 B2 (衣服上的)兜帽,风帽
part of a piece of clothing that can be pulled up to cover the top and back of the head
  The coat has a detachable hood. 这件大衣有可拆卸的风帽。 
  (为了挡住视线或不让人认出而戴的)头套,头罩
a bag that is put over someone's head so that they cannot see or be recognized
  The prisoners had been tortured and made to wear hoods. 囚犯们遭到了拷打并被强行戴上了头罩。 
 - More examples
- It's pouring - why don't you put up your hood?
- You can detach the hood if you prefer the coat without it.
  (COVER)      
  篷,罩
a part that covers or shelters a piece of equipment
  The hood over the air vent is loose. 排气口的罩子松了。 
   (CAR)      
  US (UK bonnet)(汽车的)引擎罩,发动机盖 
the metal cover over the part of a car where the engine is
  I looked under the hood and clouds of smoke poured out. 我看了一下引擎罩下面,团团的烟冒了出来。 
   (PLACE)      
 US slang (also 'hood)贫民区,贫困社区 
a poor neighbourhood
  When he started he was just a poor boy from the hood - now he's a multimillionaire. 他刚起步时只是一个从贫民区来的穷小子——如今他已是个千万富翁了。