Goblin

A goblin is a mythical creature of Germanic and British folklore, often believed to be the evil, or merely mischievous, opposite of the more benevolent faeriesand spirits of lore. Like many such creatures, there is no single version of a goblin; the term is more generic for those small creatures that live in dark places and cause trouble, but in more recent years, the term has become more concentrated on green-creatures that live in caves and terrorize children.
Despite local variations, goblins have almost universally been described as troublemakers. They are either simply tricksters and mischievous, like immature children, or malevolent, evil-doers dangerous to human beings. Like many similar creatures, they have the characteristics of spirits rather than beings existing in the physical world. Thus, they share similarities with ghosts and and also with demons as associated with some Christian teachings and lore.