Today’s word, Samhain (/ˈsˠaunʲ/) is the Irish word for November, and also refers to the ancient Celtic festival which was traditional celebrated at this time of year to mark the end of the harvest and the start of the ‘Celtic New Year’. The word samhain comes from the Old Irish samain, which possibly means ‘summer’s end’, though that etymology is uncertain.
The last day of October is known as Oíche Shamhna in Irish and Oidhche Shamhna in Scottish Gaelic, both of which mean the ‘night of Samhain’. It was a time for feasting and to for taking stock of livestock and stores of crops, a custom still observed in some areas.