The American Heritage® Dictionary of the English Language, 4th Edition
n. Any of several fishes of the family Gobiidae, especially of the genus Periophthalmus, that are found along the western coast of tropical Africa and in the Indo-Pacific region and are able to survive out of water and maneuver on land.
n. Any of various gobies of the subfamily Oxudercinae that are able to survive out of water by breathing through their skins and having strong pectoral fins that act as simple legs.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. found in tropical coastal regions of Africa and Asia; able to move on land on strong pectoral fins
Word Usage
"A better example than the mudskipper would be the coelacanths, or lobe-fin fish which, along with lungfish, diverged about the same time as tetrapods (as supported by genetic evidence)."