The definition of an amphibian is a cold-blooded animal which can live on land or in water and who breathes with gills when young and with lungs as an adult.
(noun)A frog is an example of an amphibian.
See amphibian in Webster's New World College Dictionary
noun
Origin: < ModL Amphibia < Gr amphibia, neut. pl. of amphibios: see amphibious
adjective
See amphibian in American Heritage Dictionary 4
noun
Origin:
Origin: From New Latin Amphibia, class name
Origin: , from Greek
Origin: , neuter pl. of amphibios, amphibious
Origin: : amphi-, amphi-
Origin: + bios, life; see gwei- in Indo-European roots
.Learn more about amphibian