Source : WordNet®

checkpoint
     n : a place (as at a frontier) where travellers are stopped for
         inspection and clearance

Source : Free On-Line Dictionary of Computing

checkpoint
     
        Saving the current state of a program and its data, including
        intermediate results to disk or other {non-volatile storage},
        so that if interrupted the program could be restarted at the
        point at which the last checkpoint occurred.  This facility
        came into popular use in {mainframe} {operating systems}s such
        as {OS/360} in which programs frequently ran for longer than
        the mean time between system failures.  If a program run fails
        because of some event beyond the program's control
        (e.g. hardware or {operating system} failure) then the
        processor time invested before the checkpoint will not have
        been wasted.
     
        (1995-02-07)