Plain English Meaning
The slowest speed at which the airplane will keep flying when it is going straight and level, not turning or pulling up. It is the standard stall speed shown in the aircraft manual.
Full Definition
The airspeed at which an aircraft stalls in straight, level flight at a load factor of 1G, with no turning, pull-up, or other maneuver that would increase the apparent weight on the wings. It is the baseline stall speed published in the aircraft's performance data and serves as the reference from which stall speeds at higher load factors are calculated.
Context Anchor
Seen in load factor discussions, especially when comparing straight, with , pull-ups, or other that increase the on the wings.