A movable surface, typically taking the form of a hinged flap or tab, on an aircraft for controlling its attitude or modifying the airflow over a surface.
Origin
Early 20th century.
Definition of control surface in US English:
control surface
noun
Aeronautics
A movable surface, typically taking the form of a hinged flap or tab, on an aircraft for controlling its attitude or modifying the airflow over a surface.