The Collaborative International Dictionary of English v.0.48:

Lion \Li"on\ (l[imac]"[u^]n), n. [F. lion, L. leo, -onis, akin
   to Gr. le`wn. Cf. Chameleon, Dandelion, Leopard.]
   1. (Zool.) A large carnivorous feline mammal (Panthera leo,
      formerly Felis leo), found in Southern Asia and in most
      parts of Africa, distinct varieties occurring in the
      different countries. The adult male, in most varieties,
      has a thick mane of long shaggy hair that adds to his
      apparent size, which is less than that of the largest
      tigers. The length, however, is sometimes eleven feet to
      the base of the tail. The color is a tawny yellow or
      yellowish brown; the mane is darker, and the terminal tuft
      of the tail is black. In one variety, called the maneless
      lion, the male has only a slight mane.
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   2. (Astron.) A sign and a constellation; Leo.
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   3. An object of interest and curiosity, especially a person
      who is so regarded; as, he was quite a lion in London at
      that time.
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            Such society was far more enjoyable than that of
            Edinburgh, for here he was not a lion, but a man.
                                                  --Prof.
                                                  Wilson.
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   American lion (Zool.), the puma or cougar.

   Lion ant (Zool.), the ant-lion.

   Lion dog (Zool.), a fancy dog with a flowing mane, usually
      clipped to resemble a lion's mane.

   Lion lizard (Zool.), the basilisk.

   Lion's share, all, or nearly all; the best or largest part;
      -- from Aesop's fable of the lion hunting in company with
      certain smaller beasts, and appropriating to himself all
      the prey.

   Lion of Lucerne, a famous sculptured lion at Lucerne,
      Switzerland, designed by Thorwaldsen and dedicated in 1821
      as a memorial to the Swiss Guards who fell defending Louis
      XVI. in the attack of the mob on the Tuileries, Aug. 10,
      1792. The animal, which is hewn out of the face of a rock,
      is represented as transfixed with a broken spear and
      dying, but still trying to protect with its paw a shield
      bearing the fleur-de-lis of France.

   Lion of St. Mark, a winged lion, the emblem of the
      evangelist Mark, especially that of bronze surmounting a
      granite column in the Piazzetta at Venice, and holding in
      its fore paws an open book representing St. Mark's Gospel.


   Lion of the North, Gustavus Adolphus (1594-1632), King of
      Sweden, the hero of the Protestant faith in the Thirty
      Years' War.
      [1913 Webster + Webster 1913 Suppl.]