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

xmas \x"mas\, n.
   christmas; -- an abbreviation for the christian holiday
   celebrating the birth of christ; a quarter day in england,
   wales, and ireland.

   syn: christmas, christmas day, dec 25.
        wordnet 1.5

[2] : WordNet (r) 2.0

xmas
     n : a christian holiday celebrating the birth of christ; a
         quarter day in england, wales, and ireland syn: christmas,
          christmas day, dec 25
see also:
christmas christmas day dec 25 

Xmas >> X Words
Xmas, definition of term: Xmas
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