Meaning of point of no return

point' of no' return'

Pronunciation: [key]
  1. the point in a flight at which an aircraft will lack sufficient fuel to return to its starting point.
  2. the critical point in an undertaking, decision-making process, etc., where one has committed oneself irrevocably to a course of action or policy.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.