amphibian(redirected from Amphibians)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Any of various cold-blooded, usually smooth-skinned vertebrates of the class Amphibia, characteristically hatching as an aquatic larva with gills and then transforming into an adult having air-breathing lungs. Frogs, toads, salamanders, and caecilians are amphibians.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
An animal of the class Amphibia.amphibian, adjective
Medical Dictionary, © 2009 Farlex and Partners
amphibiana member of the vertebrate class Amphibia, containing frogs, toads, newts, salamanders and the burrowing caecilians. Descended from fish-like animals, they colonized the land in the late DEVONIAN PERIOD. They are thought to be the immediate ancestors of the reptiles, though present-day amphibians are little like their Devonian ancestors. Most amphibians, although normally terrestrial animals, return to water during the breeding season. Fertilization is external (the eggs lacking a shell and embryonic membranes), and the eggs are usually laid and develop in water.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005