plural noun
Lab·​y·​rin·​tho·​don·​tia | \ -änch(ē)ə \

Definition of Labyrinthodontia

1 : a superorder of Amphibia comprising extinct amphibians of the Devonian, Upper Paleozoic, and Triassic that are extremely variable in form and size but typically resemble rather heavy-bodied salamanders or crocodiles, that have the centra of the vertebrae ossified from blocks or arches of cartilage, a completely roofed bony skull, and usually labyrinthine teeth, that are known chiefly from fragmentary remains, and that are considered to be the earliest true tetrapods and in some respects to bridge the gap between the crossopterygians and the most primitive reptiles
2 in some classifications : a subdivision of Stegocephalia that comprises forms with labyrinthine teeth and is nearly equivalent to Temnospondyli

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Other Words from Labyrinthodontia

labyrinthodontid \ ¦⸗⸗ˌ⸗⸗¦däntə̇d \ adjective or noun
labyrinthodontoid \ -​änˌtȯid \ adjective

History and Etymology for Labyrinthodontia

New Latin, from Greek labyrinthos labyrinth + New Latin -odontia

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Cite this Entry

“Labyrinthodontia.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2020.

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