noun
Aviation term for the hinged surface on the trailing edge of an aircraft wing, used to increase lift or drag.
パイロットは着陸前にフラップを下げた。
The pilot lowered the flaps before landing.
noun
Refers to the foldable part of an envelope used to seal it; also used for similar flaps on packaging.
封筒のフラップをのりで閉じた。
I sealed the envelope flap with glue.