mesopterygium

noun

mesop·​te·​ryg·​i·​um

¦me|ˌzäptəˈrijēəm,

¦mē|,

|ˌsä-

: the middle one of the three principal basal cartilages in the pectoral fins of various fishes (as the sharks and rays) compare basipterygium

Word History

Etymology

New Latin, from mes- + Greek pterygion fin, literally, small wing

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