Plain English Meaning

A signal that tells the pilot the wing is getting close to the angle where it will stop producing enough lift to fly. It can be a noise, a light, a shake in the controls, or a buffet you feel through the airframe.

Full Definition

An indication, given to the pilot before an aerodynamic stall occurs, that the wing is approaching the critical angle of attack. The warning may be aerodynamic (such as airframe buffet), or produced by a dedicated stall warning system using a horn, light, or stick shaker activated by an angle-of-attack sensor or lift detector on the wing's .