小しょう翼よく羽う

noun

alula; bastard wing

Ornithological term for the small group of feathers on the leading edge of a bird's wing, corresponding to the thumb.

• 鳥とりの小しょう翼よく羽うは、低てい速そく飛ひ行こう時じの揚よう力りょくを制せい御ぎょするのに役やく立だつ。

  The alula of a bird helps control lift during slow flight.