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

halloween \hal`loween"\ ha^l`l-o=en", n.
   the evening preceding allhallows or all saints' day november
   1; also the entire day, october 31. it is often marked by
   parties or celebrations, and sometimes by pranks played by
   young people. scot. --burns.

   syn: hallowe'en, allhallows eve.
        1913 webster + wordnet 1.5

[2] : WordNet (r) 2.0

hallowe'en
     n : the evening before all saints' day; often devoted to pranks
         played by young people syn: halloween, allhallows eve
see also:
halloween allhallows eve 

[3] : WordNet (r) 2.0

halloween
     n : the evening before all saints' day; often devoted to pranks
         played by young people syn: hallowe'en, allhallows
         eve
see also:
hallowe'en allhallows eve 

Halloween >> H Words
Halloween, definition of term: Halloween
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