n. A fish which lives or burrows in the mud. Specifically — A dipnoan fish, Protopterus annectens, of the family Lepidosirenidæ.n. The Australian Ceratodus forsteri.n. The North American bowfin, Amiacalva. Also called marsh fish.n. Some or any species of the genus Umbra or family Umbridæ. Also called mud-minnow.n. A former Anglo-American name in New York of a killifish.n. A gobiine fish, Gillichthys mirabilis, remarkable for the great extension backward of the maxillary bones. It attains a length of 6 inches, and burrows in the mud between tide-marks, so that its burrow is exposed at low tide. It abounds along the coast of California.n. A New Zealand fish of the family Galaxiidæ; the Neochanna apoda. P. L. Sclater. (See cuts under Amiidæ, Lepidosiren, Umbra, and Gillichthys.)