Source : Webster's Revised Unabridged Dictionary (1913)

Long-winded \Long"-wind"ed\, a.
   Long-breathed; hence, tediously long in speaking; consuming
   much time; as, a long-winded talker. -- {Long"-wind"ed*ness},
   n.

         A tedious, long-winded harangue.         --South.

Source : WordNet®

long-windedness
     n : boring verboseness [syn: {prolixity}, {prolixness}, {wordiness}]