Lungworm
The lungworm is a type of parasite. It lives inside other animals' bodies.  Lungworms are roundworms in the order Strongylida.  They have round bodies.  When people say the word "lungworm," they may mean any of a few worms: Eucoleus aerophilus, Oslerus osleri, Crenostoma vulpis, Eucoleus boehmi, or Filaroides hirthi. Some people also use it for Angiostrongylus vasorum, but that worm is really a heartworm.