Complex sentence: The term "nuckelavee" is a corruption of the Orcadian "knoggelvi", but the same demon is called a "mukkelevi" in Shetland, where it was considered a nasty sea trow or sea devil.
Split into simpler sentences: The term "nuckelavee" is a corruption of the Orcadian "knoggelvi". The same demon is called a "mukkelevi" in Shetland, where it was considered a nasty sea trow or sea devil.