In Norse mythology, Hati Hróðvitnisson (first name meaning "He Who Hates, Enemy") is a wolf that according to Gylfaginning chases the Moon across the night sky, just as the wolf Sköll chases the Sun during the day, until the time of Ragnarök when they will swallow these heavenly bodies, after which Fenrir will break free from his bonds and kill Odin.
Hati's surname is Hróðvitnisson, attested in both Grímnismál and Gylfaginning, which indicates that he is the son of Fenrir, whose alternate name is Hróðvitnir ("Famous Wolf"). Hati's mother is the giantess, not named but mentioned in Völuspá and Gylfaginning, who dwells to the east of Midgard in the forest of Járnviðr ("Ironwood"). Snorri Sturluson states that this giantess and witch bears many giants for sons, all in the form of wolves including one named Mánagarm ("Moon Hound") who shall swallow the Moon and is thus identified with Hati. From this passage it is also presumed that Sköll is Hati's brother.