Plain English Meaning
The fastest speed at which you can yank a control to its stop and trust the airplane will stall before it breaks. Above this speed, hard control inputs or strong gusts can overstress the airframe.
Full Definition
The maximum airspeed at which abrupt or full deflection of a single flight control will cause the airplane to stall before exceeding its structural load limits. Often shown as VA in the Pilot's Operating Handbook, it varies with aircraft weight and is published for one or more specific weights.
Context Anchor
Seen in the airplane handbook and in maneuver discussions such as , where speed, turning , and structural limits .