Evil monsters of Greek Christmas foklore whose description varies — in some places they are viewed as half-human with hoofs and claws, in others they are wolf-like or simian. They spend most of the year in the underworld, chopping away at the tree that supports the earth. This tree is renewed at Christmas by the birth of Christ so the demons come to earth for revenge: they urinate on fires, ride on folks’ backs, force them to dance to exhaustion and commit other enormities. They may be kept out of the chimney (through which they enter) by keeping the Christmas log alight or by burning salt or old shoes whose smell repels them; the lower jaw of a pig or certain herbs such as hyssop hung behind the door or inside the chimney will also keep them out. They roam the earth until January 6 when the Blessing of the Waters drives them underground.
Any child born during Christmas is in danger of becoming one of the kallikantzaroi; to prevent this the child must be bound in tresses of garlic or straw or have his toenails singed.