Source : Webster's Revised Unabridged Dictionary (1913)

Madhouse \Mad"house`\, n.
   A house where insane persons are confined; an insane asylum;
   a bedlam.

Source : WordNet®

madhouse
     n : pejorative terms for an insane asylum [syn: {Bedlam}, {booby
         hatch}, {crazy house}, {cuckoo's nest}, {funny farm}, {funny
         house}, {loony bin}, {nut house}, {nuthouse}, {sanatorium},
          {snake pit}]