The Collaborative International Dictionary of English v.0.48:

Long-winded \Long"-wind"ed\, a.
   1. Long-breathed; hence, tediously long in speaking;
      consuming much time; as, a long-winded talker.
      [1913 Webster]

            A tedious, long-winded harangue.      --South.
      [1913 Webster]

   2. using or containing too many words; as, long-winded (or
      windy) speakers.

   Syn: tedious, verbose, windy, wordy.
        [WordNet 1.5] -- Long"-wind"ed*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

long-windedness
    n 1: boring verbosity [syn: prolixity, prolixness,
         windiness, long-windedness, wordiness]