Hyperotreta \Hy`per*o*tre"ta\, n. pl. [NL., fr. Gr. ? the plate + ? perforated.] (Zo["o]l.) An order of marsipobranchs, including the Myxine or hagfish and the genus {Bdellostoma}. They have barbels around the mouth, one tooth on the plate, and a communication between the nasal aperture and the throat. See {Hagfish}. [Written also {Hyperotreti}.]