Norse Mythology: A giant. He became a member of the Aesir when Odin made Loki his blood brother. He is the god of mischief, a trickster, and very cunning. After causing the death of Balder, he was bound by the gods until the Ragnarok, at which time, he will be freed. There are quite a few sites dealing with Loki including a wonderful on-line essay by Johannes Persson, an article by Eric A. Anderson regarding Loki's offspring, and the Loki Cult Web Page.
(Nicole Cherry, A list of Norse Beings, http://www.ugcs.caltech.edu/~cherryne)