roach  
noun [ C ] uk/rəʊtʃ/ us/roʊtʃ/
  (FISH)     
  plural roach(产于欧洲的)斜齿鳊,拟鲤 
a European fish that lives in fresh water
   (INSECT)     
  US plural roaches蟑螂(cockroach的非正式说法) 
informal for cockroach 
   (CIGARETTE)     
 slang plural roaches(大麻烟卷的)烟蒂 
a piece of card or other material used to make the end part of a joint (= cannabis cigarette) or roll-up (= hand-made cigarette), that the smoke is breathed through