Definitions for "escape velocity"
The minimum velocity at which an object must be moving in order for it to overcome the gravitational attraction of a massive celestial body, such as the earth or the sun, and escape beyond its gravitational field into free space. The velocity is calculated as though attained instantaneously at the surface of the celestial body, and is pointed directly away from its center, and neglecting effects of atmospheric friction. Rockets, which accelerate gradually and are moving rapidly at a high altitude when their fuel is exhausted or their engines shut off, may escape even if moving slightly slower at that point than the surface escape velocity. Compare orbital velocity.
The speed necessary to escape the gravity of a massive body
The velocity required for an object to escape the gravitational field of a body such as a planet .In a more technical sense, the escape velocity is the velocity at which the kinetic energy of the object equals its gravitational potential energy; if the object moves any faster, its kinetic energy exceeds its potential energy, and the object can escape the gravitational field.
The first book in the Warlock of Gramarye series by Christopher Stasheff, released in 1983.