Halloween is a noun and short for All Hallows. It is also October 31 observed particularly with dressing up in disguise, trick-or-treating, and displaying jack-o’-lanterns during the evening. The word originally from the word Hallow, which means to make or set apart as holy or to revere or respect greatly. Hallow originated from Middle English word Halwen, and old English Halgian. An example is Wilkie Collins:
I lift up one of the baby’s hands, and put the letter under it–and so associate that dreadful record of sin and misery with something innocent and pretty that seems to hallow and to purify it.
Halloween, All saints day, All hallows eve or All souls day is a celebration. It was held to honor the Samhain the “lord of death”. It was a Druidical faith that on the eve of this festival Samhain, lord of death, called together the wicked spirits that within the past 12 months had been condemned to occupy the bodies of animals.
According to another source it was a pagan belief that on one night of the year the souls of the dead return to their original homes, there to be entertained with foodstuff. If food and shelter were not offered, these evil spirits would cast spells and cause havoc toward those failing to fulfill their wishes. Sacrifices were offered on this night to the dead spirits because it was thought they visited their earthly dwellings and previous friends.