Buffet is a distinct physical shaking of the airframe that occurs just before or during an aerodynamic stall. It happens when smooth airflow over the wings breaks away, creating turbulent wakes that strike the tail surfaces. Pilots rely on this tactile feedback as a natural warning that the wing is losing lift and requires an immediate reduction in angle of attack.
Heard on the job
I felt the buffet start at around 80 knots, so I pushed the nose down to recover.
Insider tip
Older aircraft rely on natural aerodynamic buffet to warn the pilot of a stall, while newer fly-by-wire jets use a mechanical stick shaker to simulate the exact same feeling.