Lobster \Lob"ster\, n. [AS. loppestre, lopystre prob., corrupted
   fr. L. locusta a marine shellfish, a kind of lobster, a
   locust. Cf. {Locust}.] (Zool.)
   1. Any large macrurous crustacean used as food, esp. those of
      the genus {Homarus}; as the American lobster ({Homarus  Americanus}), and the European lobster ({Homarus  vulgaris}). The Norwegian lobster ({Nephrops Norvegicus})
      is similar in form. All these have a pair of large unequal
      claws. The spiny lobsters of more southern waters,
      belonging to {Palinurus}, {Panulirus}, and allied genera,
      have no large claws. The fresh-water crayfishes are
      sometimes called lobsters.
      
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   2. As a term of opprobrium or contempt: A gullible, awkward,
      bungling, or undesirable person. [Slang]
      [Webster 1913 Suppl.]

   {Lobster caterpillar} (Zool.), the caterpillar of a European
      bombycid moth ({Stauropus fagi}); -- so called from its
      form.

   {Lobster louse} (Zool.), a copepod crustacean ({Nicothoe  astaci}) parasitic on the gills of the European lobster.
      
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