chum in WordNet English dictionary

1. a close friend who accompanies his buddies in their activities
   buddy  brother  chum  crony  pal  sidekick 
   
2. a large Pacific salmon with small spots on its back; an important food fish
   chum salmon  chum  Oncorhynchus keta 
   
3. bait consisting of chopped fish and fish oils that are dumped overboard to attract fish
   chum