The Collaborative International Dictionary of English v.0.48:

Poetry \Po"et*ry\, n. [OF. poeterie. See Poet.]
   1. The art of apprehending and interpreting ideas by the
      faculty of imagination; the art of idealizing in thought
      and in expression.
      [1913 Webster]

            For poetry is the blossom and the fragrance of all
            human knowledge, human thoughts, human passions,
            emotions, language.                   --Coleridge.
      [1913 Webster]

   2. Imaginative language or composition, whether expressed
      rhythmically or in prose. Specifically: Metrical
      composition; verse; rhyme; poems collectively; as, heroic
      poetry; dramatic poetry; lyric or Pindaric poetry. "The
      planetlike music of poetry." --Sir P. Sidney.
      [1913 Webster]

            She taketh most delight
            In music, instruments, and poetry.    --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

poetry
    n 1: literature in metrical form [syn: poetry, poesy,
         verse]
    2: any communication resembling poetry in beauty or the
       evocation of feeling

The Devil's Dictionary (1881-1906):

POETRY, n.  A form of expression peculiar to the Land beyond the
Magazines.