Meaning of escape velocity

escape' veloc"ity

Pronunciation: [key]
— Physics, Rocketry. Physics,Rocketry.
  1. the minimum speed that an object at a given distance from a gravitating body must have so that it will continue to move away from the body instead of orbiting about it.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.