Source : Webster's Revised Unabridged Dictionary (1913)

Wren \Wren\ (r[e^]n), n. [OE. wrenne, AS. wrenna, wr[ae]nna,
   perhaps akin to wr[=ae]ne lascivious.]
   1. (Zo["o]l.) Any one of numerous species of small singing
      birds belonging to {Troglodytes} and numerous allied of
      the family {Troglodytid[ae]}.

   Note: Among the species best known are the house wren
         ({Troglodytes a["e]don}) common in both Europe and
         America, and the American winter wren ({T. hiemalis}).
         See also {Cactus wren}, {Marsh wren}, and {Rock wren},
         under {Cactus}, {Marsh}, and {Rock}.

   2. (Zo["o]l.) Any one of numerous species of small singing
      birds more or less resembling the true wrens in size and
      habits.

   Note: Among these are several species of European warblers;
         as, the reed wren (see {Reed warbler}
      (a), under {Reed}), the sedge wren (see {Sedge warbler},
          under {Sedge}), the willow wren (see {Willow warbler},
          under {Willow}), the golden-crested wren, and the
          ruby-crowned wren (see {Kinglet}).

   {Ant wren}, any one of numerous South American birds of the
      family {Formicarid[ae]}, allied to the ant thrushes.

   {Blue wren}, a small Australian singing bird ({Malurus
      cyaneus}), the male of which in the breeding season is
      bright blue. Called also {superb warbler}.

   {Emu wren}. See in the Vocabulary.

   {Wren babbler}, any one of numerous species of small timaline
      birds belonging to {Alcippe}, {Stachyris}, {Timalia}, and
      several allied genera. These birds are common in Southern
      Asia and the East Indies.

   {Wren tit}. See {Ground wren}, under {Ground}.

   {Wren warbler}, any one of several species of small Asiatic
      and African singing birds belonging to {Prinia} and allied
      genera. These birds are closely allied to the tailor
      birds, and build their nests in a similar manner. See also
      {Pincpinc}.

Source : WordNet®

Wren
     n 1: English architect who designed more than fifty London
          churches (1632-1723) [syn: {Sir Christopher Wren}]
     2: and of several small active brown birds of the northern
        hemisphere with short upright tails; they feed on insects
        [syn: {jenny wren}]