Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
labyrinthodontany primitive amphibians of the order Labyrinthodontia, which existed from the Devonian to the Triassic. They are related to Crossopterygian fish and some are close to the reptiles.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005