Plagiostomi

plural noun

Pla·​gi·​os·​to·​mi

ˌplājēˈästəˌmī

in some especially former classifications

: a group of fishes more or less exactly equivalent to Chondrichthyes or more restrictedly an order including the existing sharks and rays as distinguished from the chimaeras and the extinct primitive groups Pleuropterygii and Ichthyotomi compare selachii

Word History

Etymology

New Latin, from plagi- + -stomi

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