nuckelavee

thumb|240px|alt=Tammas flees the nuckelavee|The nuckelavee chasing an islander, painting by James Torrance (1859–1916). The nuckelavee () or nuckalavee is a horse-like demon from Orcadian folklore that combines equine and human elements. If one was looking casually, or under the cover of shadow in the night, it was thought to have the silhouette of a normal horseman. However, upon further inspection, it resembles a fleshless horse which sports one eye and fins on its legs, with a fleshless human head, torso, and arms longer than normal sprouting out the horse's back.

British folklorist Katharine Briggs called it "the nastiest" of all the demons of Scotland's Northern Isles. The nuckelavee's breath was thought to wilt crops and sicken livestock and the creature was held responsible for droughts and epidemics on land despite being predominantly a sea-dweller.