Definition of propatagium in English:

propatagium

noun

Zoology
  • In bats, gliding mammals, pterosaurs, etc.: the part of the patagium (the wing or gliding membrane) anterior to the forelimb. In birds: the fold of skin running between the shoulder and the front edge of the wing.

Origin

Late 19th century; earliest use found in Philosophical Transactions of the Royal Society of London. From scientific Latin propatagium from pro- + patagium.