tetrapod

noun

tet·​ra·​pod ˈte-trə-ˌpäd How to pronounce tetrapod (audio)
: a vertebrate (such as an amphibian, a bird, or a mammal) with two pairs of limbs

Did you know?

The earliest tetrapods, or "four-footed" animals, were mammal-like reptiles that evolved before the rise of the dinosaurs and ranged from mouse-sized to cow-sized. Today the tetrapods include the reptiles, the amphibians, the birds, and the mammals—including humans. Though the fish aren't classified as tetrapods, it's quite possible that our own limbs began as paired fins hundreds of millions of years ago.

Examples of tetrapod in a Sentence

Recent Examples on the Web During the Carboniferous Period, the evolutionary adaption of the amniote egg allowed the early tetrapods to lay their eggs on land — allowing the species to transition to a fully on-land lifestyle, according to the University of California Museum of Paleontology. Elizabeth Gamillo, Discover Magazine, 11 Jan. 2024 While most tetrapods — which includes all four-limbed, land-living vertebrates, such as frogs, turtles, hawks and humans — have five digits or fewer, the distant ancestors of amphibians, mammals, birds and reptiles used to have more. Joshua Rapp Learn, Discover Magazine, 19 Sep. 2023 At some point, four-legged tetrapods that had lived in the water some 300 million years ago decided to submerge themselves once again, perhaps to avoid predators. Matt Hrodey, Discover Magazine, 10 Aug. 2023 Multiple losses of opsin genes have occurred as tetrapods—a group including amphibians, reptiles, and mammals—have evolved. Laura Baisas, Popular Science, 12 July 2023 In addition to the latter’s markings, the team found three different pathways marked by small footprints that probably belonged to smaller tetrapods that had waded through the water. Matt Hrodey, Discover Magazine, 30 Mar. 2023 An excavation exposed a wall of fossils there in 2016, during road construction, and led to this and a number of other discoveries, including the fossil of an early tetrapod, the massive fish’s likely prey. Matt Hrodey, Discover Magazine, 7 Mar. 2023 Our moon’s tides most likely played a role in evolution, shepherding the first plants and tetrapods from the salty marshes of the coasts and onto land. Rebecca Boyle, Scientific American, 1 Mar. 2021 But Eusthenopteron foordi, another stem tetrapod that comes after Paleospondylus, had paired fins and cranial development even in juveniles. Connor Lynch, Discover Magazine, 20 June 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'tetrapod.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin tetrapodus, from Greek tetrapod-, tetrapous four-footed, from tetra- + pod-, pous foot — more at foot

First Known Use

circa 1891, in the meaning defined above

Time Traveler
The first known use of tetrapod was circa 1891

Dictionary Entries Near tetrapod

Cite this Entry

“Tetrapod.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tetrapod. Accessed 28 Mar. 2024.

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