plural noun
Tri·​onych·​i·​dae | \ ˌtrīəˈnikəˌdē\

Definition of Trionychidae

: a family of freshwater softshell turtles containing both fossil Tertiary and living forms in which the horny plates of carapace and plastron are replaced by leathery skin and constituting a distinct superfamily of Cryptodira

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History and Etymology for Trionychidae

New Latin Trionych-, Trionyx, type genus + -idae

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readily or continually undergoing change

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