Plain English Meaning
Lights or on-screen messages in the cockpit that tell the pilot when something needs attention. For stalls, it’s the warning light that comes on before the wing stops flying.
Full Definition
Cockpit warning indicators—typically illuminated panels, lights, or messages on a display—that alert the pilot to a specific condition, such as an impending stall, low fuel, or a system fault. In the context of stalls, an annunciator is the visual portion of the stall warning system that activates before the wing reaches the critical angle of attack.