Definition
A noticeable shaking or vibration of the airframe and flight controls that occurs as the wing approaches the critical angle of attack, caused by turbulent, separated airflow leaving the upper wing surface and striking the tail and other downstream structures. It is an aerodynamic warning that a stall is imminent.
Plain English
A shudder you feel through the airplane just before it stalls, caused by rough air coming off the wing and hitting the tail. It is the airplane physically warning you that the wing is about to stop flying.
Context Anchor
Seen in stall training, accelerated stall discussions, steep turns, and any situation where the wing is asked to produce lift at a high angle to the airflow.
Derivation
Stall comes from the older sense of an engine or motion stopping. Buffet, from the Old French buffeter, means to strike or knock repeatedly. Together the term describes the repeated aerodynamic knocking the airplane feels as the wing nears the stall.
Why Pilots Care
It gives an unmistakable tactile warning of an impending stall, allowing recovery before full loss of lift and control.
Intuition Check
Do not read buffet as a meal or gentle vibration. In this context, buffet means shaking caused by disturbed airflow; and stall refers to the wing losing smooth lift, not the engine quitting.
Example Sentence 1
As she tightened the steep turn, the pilot felt the stall buffet and immediately relaxed back-pressure to reduce the angle of attack.
Example Sentence 2
The instructor asked the student to recover at the first sign of stall buffet rather than waiting for the full stall.