[1] : The Collaborative International Dictionary of English v.0.48

madhouse \mad"house`\, n.
   1. an house or institution where insane persons are confined;
      an insane asylum; a bedlam; -- usually used in a
      deprecatory sense.

   syn: bedlam, booby hatch, crazy house, cuckoo's nest, funny
        farm, funny house, insane asylum, loony bin, nuthouse,
        sanatorium.
        1913 webster

   2. hence: fig. a chaotic, raucus or highly disordered
      situation.
      pjc

[2] : WordNet (r) 2.0

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
see also:
bedlam booby hatch crazy house cuckoo's nest funny farm funny house 
loony bin nut house nuthouse sanatorium snake pit 

Madhouse >> M Words
Madhouse, definition of term: Madhouse
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