#porpoise  any of several small gregarious cetacean mammals having a blunt snout and many teeth
  supertype:  dolphin  any of various small toothed whales with a beaklike snout; larger than porpoises
  member of:  genus_Phocaena
  subtype:  harbor_porpoise__herring_hog__Phocaena_phocaena  the common porpoise of the North Atlantic and Pacific

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