hyperotreta

from The Century Dictionary.

• A primary subdivision of myzonts, embracing forms with the roof of the mouth perforated by the single nasal canal.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural (Zoöl.) An order of marsipobranchs, including the Myxine or hagfish and the genus Bdellostoma. They have barbels around the mouth, one tooth on the palate, and a communication between the nasal aperture and the throat. See hagfish.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun hagfishes as distinguished from lampreys