Definition
The rear edge of an airfoil, where airflow from the upper and lower surfaces rejoins after passing over the wing. It is the aft-most line of the wing, stabilizer, or control surface.
Plain English
The back edge of the wing — the thin edge that points toward the tail of the airplane.
Context Anchor
Seen in wing diagrams, angle-of-attack discussions, and preflight inspections of the wing’s rear edge.
Derivation
‘Trailing’ comes from the Old French ‘trailler,’ meaning to drag or follow behind. The trailing edge is the edge that follows behind as the wing moves through the air — the opposite of the leading edge, which goes first.
Why Pilots Care
Control surfaces such as ailerons, elevators, and flaps are attached along the trailing edge; damage or improper rigging here directly affects roll, pitch, and lift control.
Intuition Check
Do not think of trailing edge as a loose or dragging part. It means the fixed rear edge of the wing or blade—the edge the airflow reaches last.
Example Sentence 1
When the flaps are lowered, the trailing edge of the wing drops, increasing lift at slower airspeeds.
Example Sentence 2
Ailerons are hinged along the trailing edge so they can change the wing's camber when deflected.