alula

plural alulae · plural alulas

1. biologyA small projection of three or four feathers on the first digit of the wing on some birds.First known use 18th c.

   On the wing, even the tiny “thumb feather” or alula can be seen.

   2017 June 28, Hanneke Meijer, The Guardian

   1 more example

   More recently, the upturned wing tips of jet aircraft mimic the "fingers" of birds' terminal primary feathers, and the slotted leading edges of aircraft wings are directly copied from the alula ("thumb" wings) in birds.

   2021, Peter Cavanagh, “Preface”, in 100 Flying Birds: Photographing the Mechanics of Flight, →ISBN, page 10

   Synonyms: bastard wing

plural alulas

1. A flower, a species of Hawaiian lobelioid.

   Synonyms: vulcan palm, cabbage on a stick, Brighamia insignis, B. insignis, insignis