Source : Webster's Revised Unabridged Dictionary (1913)

Lied \Lied\ (l[=e]t), n.; pl. {Lieder} (l[=e]"d[~e]r). [G.]
   (Mus.)
   A lay; a German song. It differs from the French chanson, and
   the Italian canzone, all three being national.

         The German Lied is perhaps the most faithful reflection
         of the national sentiment.               --Grove.

Source : WordNet®

lied
     n : a German art song of the 19th century for voice and piano
     [also: {lieder} (pl)]

lieder
     See {lied}