Frog \Frog\ (fr[o^]g), n. [AS. froggu, frocga a frog (in
  
         sensel); akin to D. vorsch, OHG. frosk, G. frosch, Icel.
  
         froskr, fraukr, Sw. & Dan. fr["o].]
   1. (Zool.) An
         amphibious animal of the genus Rana and
      related
         genera, of many species. Frogs swim rapidly, and
      take
         long leaps on land. Many of the species utter loud
     
         notes in the springtime.
      [1913 Webster]

   Note:
         The edible frog of Europe (Rana esculenta) is
         extensively used as food; the American bullfrog (R. Catesbiana) is
         remarkable for its great size and loud
         voice.
         [1913 Webster]

   2. [Perh. akin to E. fork, cf. frush
         frog of a horse.]
      (Anat.) The triangular prominence
         of the hoof, in the
      middle of the sole of the foot of
         the horse, and other
      animals; the fourchette.
     
         [1913 Webster]

   3. (Railroads) A supporting plate
         having raised ribs that
      form continuations of the
         rails, to guide the wheels where
      one track branches
         from another or crosses it.
      [1913 Webster]

   4.
         [Cf. fraco of wool or silk, L. floccus, E. frock.] An
     
         oblong cloak button, covered with netted thread, and
     
         fastening into a loop instead of a button hole.
      [1913
         Webster]

   5. The loop of the scabbard of a bayonet or
         sword.
      [1913 Webster]

   Cross frog (Railroads),
         a frog adapted for tracks that
      cross at right
         angles.

   Frog
         cheese, a popular name for a large
         puffball.

   Frog
         eater, one who eats frogs; -- a term
         of contempt
      applied to a Frenchman by the vulgar
         class of English.

   Frog fly. (Zool.) See Frog
         hopper.

   Frog
         hopper (Zool.), a small, leaping,
         hemipterous insect
      living on plants. The larv[ae] are
         inclosed in a frothy
      liquid called cuckoo spit or
         frog spit.

   {Frog
         lily} (Bot.), the yellow water lily
         (Nuphar).

   {Frog
         spit} (Zool.), the frothy exudation
         of the frog hopper;
         -- called also frog
         spittle.
         See Cuckoo spit,
  
            under Cuckoo.
     
         [1913
         Webster]