point of no return
- the moment on a flight when there is no longer enough fuel to return to the starting point
- a point in an enterprise, adventure, etc. when participants are too deeply involved or committed to withdraw
See point of no return in American Heritage Dictionary 4
noun pl. points of no return
- The point in a course of action beyond which reversal is not possible.
- The point in the flight of an aircraft beyond which there is insufficient fuel for return to the starting point.
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