1. An ancient Celtic feast celebrating the end of harvest and the beginning of winter, marked by bonfires and sacrifices and by the propitiation of gods who were believed to become visible and play tricks on their worshipers.
2. The period during which this feast was held, usually the evening of October 31 and the day of November 1.
[Irish Samhain, from Old Irish samain; see sem-2 in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.