plural noun

: a family of Carboniferous and Permian elasmobranchs (subclass Holocephali) related to the rays and having peculiar flattened petaloid teeth and greatly enlarged pectoral fins see petalodus

Word History


New Latin, from Petalodont-, Petalodus, type genus + -idae

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Dictionary Entries Near Petalodontidae

Cite this Entry

“Petalodontidae.” Dictionary, Merriam-Webster, Accessed 2 Dec. 2023.

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