1. A Christian feast commemorating the birth of Jesus.
2. December 25, the day on which this feast is observed as a public holiday in many countries.
[Middle English Cristemas, from Old English Crīstes mæsse, Christ's festival : Crīst, Christ; see CHRIST + mæsse, festival; see MASS.]
Christmas·sy, Christmas·y adj.
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Indo-European & Semitic Roots Appendices
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