What is "musmahhu"

Mušmaḫḫū, inscribed in Sumerian as MUŠ.MAḪ, Akkadian as muš-ma-ḫu, meaning “Exalted/distinguished Serpent,” was an ancient Mesopotamian mythological hybrid of serpent, lion and bird, sometimes identified with the seven-headed serpent slain by Ninurta in the mythology of the Sumerian period. He is one of the three horned snakes, with his companions, Bašmu and Ušumgallu, with whom he may have shared a common mythological origin.