Definition
A combination of movable wing devices — typically flaps, and on some aircraft slats, slots, or leading-edge devices — designed to temporarily increase the wing's lift at low airspeeds. These devices change the shape and/or area of the wing so the airplane can fly safely at slower speeds during takeoff, approach, and landing.
Plain English
Parts of the wing that the pilot can extend to make the wing produce more lift at slow speeds, so the airplane can take off and land without stalling.
Context Anchor
Seen in discussions of takeoff, landing, slow flight, and airplane systems that change wing performance.
Derivation
"High-lift" simply means "producing a lot of lift." The phrase exists because the wing alone, in its clean (retracted) shape, cannot produce enough lift at low speeds — these devices are added to give the wing a temporary high-lift configuration when needed.
Why Pilots Care
High-lift systems shorten required runway distances and allow safe operation at lower approach and departure speeds.
Grounding Statement
When the pilot extends the high-lift system, the wing is being adjusted to work better at slower speeds.
Intuition Check
High-lift does not mean the airplane automatically climbs higher. It means the wing can make the lift it needs at a lower speed.
Example Sentence 1
Before landing, the pilot extended the high-lift system to allow a slower, more stable approach speed.
Example Sentence 2
On final approach the high-lift system was fully extended to maintain lift while the airspeed was reduced for landing.