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definitions

winglet

[wing-lit]

noun

a little wing.
Zoology. alula.
Aeronautics.
  1. a small wing used mainly to carry external loads or to connect struts or gears to the fuselage.
  2. a short, near-vertical projection on a wing tip that reduces drag and improves fuel efficiency.

Origin of winglet

First recorded in 1605–15; wing + -let
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for winglet

winglet

noun

a small wing, esp the bastard wing of a bird
a small wing placed at the tip of the main wing of an aircraft and perpendicular to it designed to reduce the aircraft's vortex drag
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012