The Collaborative International Dictionary of English v.0.48:

Song \Song\ (s[o^]ng; 115), n. [AS. song, sang, fr. singan to
   sing; akin to D. zang, G. sang, Icel. s["o]ngr, Goth. saggws.
   See Sing.]
   1. That which is sung or uttered with musical modulations of
      the voice, whether of a human being or of a bird, insect,
      etc. "That most ethereal of all sounds, the song of
      crickets." --Hawthorne.
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   2. A lyrical poem adapted to vocal music; a ballad.
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   3. More generally, any poetical strain; a poem.
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            The bard that first adorned our native tongue
            Tuned to his British lyre this ancient song.
                                                  --Dryden.
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   4. Poetical composition; poetry; verse.
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            This subject for heroic song.         --Milton.
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   5. An object of derision; a laughingstock.
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            And now am I their song, yea, I am their byword.
                                                  --Job xxx. 9.
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   6. A trifle; an insignificant sum of money; as, he bought it
      for a song. "The soldier's pay is a song." --Silliman.
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   Old song, a trifle; nothing of value. "I do not intend to
      be thus put off with an old song." --Dr. H. More.

   Song bird (Zool.), any singing bird; one of the Oscines.


   Song sparrow (Zool.), a very common North American sparrow
      (Melospiza fasciata, or Melospiza melodia) noted for
      the sweetness of its song in early spring. Its breast is
      covered with dusky brown streaks which form a blotch in
      the center.

   Song thrush (Zool.), a common European thrush (Turdus
      musicus), noted for its melodius song; -- called also
      mavis, throstle, and thrasher.
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   Syn: Sonnet; ballad; canticle; carol; canzonet; ditty; hymn;
        descant; lay; strain; poesy; verse.
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The Collaborative International Dictionary of English v.0.48:

Mavis \Ma"vis\ (m[=a]"v[i^]s), n. [F. mauvis, Arm. milvid,
   milfid, milc'hhouid, Corn. melhuez.] (Zool.)
   The European throstle or song thrush (Turdus musicus).
   [1913 Webster] Mavournin

The Collaborative International Dictionary of English v.0.48:

Thrush \Thrush\, n. [OE. [thorn]rusche, AS. [thorn]rysce; akin
   to OHG. drosca, droscea, droscela, and E. throstle. Cf.
   Throstle.]
   1. (Zool.) Any one of numerous species of singing birds
      belonging to Turdus and allied genera. They are noted
      for the sweetness of their songs.
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   Note: Among the best-known European species are the song
         thrush or throstle (Turdus musicus), the missel
         thrush (see under Missel), the European redwing, and
         the blackbird. The most important American species are
         the wood thrush (Turdus mustelinus), Wilson's thrush
         (Turdus fuscescens), the hermit thrush (see under
         Hermit), Swainson's thrush (Turdus Aliciae), and
         the migratory thrush, or American robin (see Robin).
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   2. (Zool.) Any one of numerous species of singing birds more
      or less resembling the true thrushes in appearance or
      habits; as the thunderbird and the American brown thrush
      (or thrasher). See Brown thrush.
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   Ant thrush. See Ant thrush, Breve, and Pitta.

   Babbling thrush, any one of numerous species of Asiatic
      timaline birds; -- called also babbler.

   Fruit thrush, any species of bulbul.

   Shrike thrush. See under Shrike.

   Stone thrush, the missel thrush; -- said to be so called
      from its marbled breast.

   Thrush nightingale. See Nightingale, 2.

   Thrush tit, any one of several species of Asiatic singing
      birds of the genus Cochoa. They are beautifully colored
      birds allied to the tits, but resembling thrushes in size
      and habits.

   Water thrush.
      (a) The European dipper.
      (b) An American warbler (Seiurus Noveboracensis).
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