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

loony bin \loony bin\ l=oon"y^ bi^n n.
   an institution for the confinement or treatment of insane
   persons, such as an insane asylum or the psychiatric ward of
   a hospital. slang

   syn: mental institution.
        pjc

[2] : WordNet (r) 2.0

loony bin
     n : pejorative terms for an insane asylum syn: bedlam, booby
         hatch, crazy house, cuckoo's nest, funny farm, funny
         house, madhouse, nut house, nuthouse, sanatorium,
          snake pit
see also:
bedlam booby hatch crazy house cuckoo's nest funny farm funny house 
madhouse nut house nuthouse sanatorium snake pit 

Bin >> B Words
Bin, definition of term: Bin
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