noun pty·cho·pterygium \"+\

Definition of ptychopterygium



  1. :  a primitive fin consisting of a low triangular flap supported by a series of unbranched rays

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Origin and Etymology of ptychopterygium

New Latin, from ptych- + Greek pterygion little wing, fin — more at pterygium

Seen and Heard

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a rounded knoll or a ridge of ice

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