amphibian

noun

am·​phib·​i·​an am-ˈfi-bē-ən 

1

: an amphibious organism

especially : any of a class (Amphibia) of cold-blooded vertebrates (such as frogs, toads, or salamanders) intermediate in many characters between fish and reptiles and having gilled aquatic larvae and air-breathing adults

Unlike reptiles, most amphibians possess a smooth, moist skin and lay their shell-less eggs in water or wet places.

—Jeffrey P. Cohn

2

: an amphibious vehicle

especially : an airplane designed to take off from and land on either land or water

amphibian adjective

Examples of amphibian in a Sentence

Recent Examples on the Web

Because birds and amphibians are only distantly related to sea turtles, Goforth and her colleagues think that magnetic compasses and maps might be a common feature in the vertebrate travel toolbox. —Jack Tamisiea, Scientific American, 12 Feb. 2025

Join 2 others in the comments View Comments This latest research reveals that, similar to birds and amphibians, turtles also rely on dual magnetoreception systems, which could provide further insights into other migratory vertebrates. —Julianna Bragg, CNN, 12 Feb. 2025

But immediately, the lack of shade will harm sensitive animals most prone to drying out, like mollusks and amphibians. —Anton Sorokin, Smithsonian Magazine, 5 Feb. 2025

Thanks to Baum’s work, Jockey’s Ridge remains hospitable to more than 160 types of birds, and 38 types of reptiles and amphibians call it home, along with otters, coyotes, foxes, rabbits and even at least one bobcat. —Amy Brecount White, Smithsonian Magazine, 6 May 2025

Word History

Etymology

New Latin Amphibia, taxon including frogs and salamanders (from neuter plural of amphibius amphibious) + -an entry 1

Note: As a taxon Amphibia was used as a class name already by linnaeus (Systema naturae, 10. editio, 1758, p. 196 et passim), but in a sense that included both amphibians and some reptiles. Limitation of the taxon to approximately its current meaning dates from Thomas Gray's "A Synopsis of the Genera of Reptiles and Amphibia" (Annals of Philosophy, new series vol. 10, July-December, 1825, pp.193-217) according to Darrel R. Frost, et al., "The Amphibian Tree of Life," Bulletin of the American Museum of Natural History, No. 297 (2006), p. 355. The use of both English amphibian and Latin amphibius with varying gender and number to refer to animals living on both land and sea (and in figurative senses) can be found much earlier.

First Known Use

1749, in the meaning defined at sense 1

Rhymes for amphibian

• caribbean
• libyan

Kids Definition

amphibian

noun

am·​phib·​i·​an am-ˈfib-ē-ən 

1

: any organism that is able to live both on land and in water

especially : any of a class of cold-blooded vertebrate animals (as frogs and salamanders) that in many respects are between fishes and reptiles

2

: an airplane designed to take off from and land on either land or water

amphibian adjective