The Jargon File (version 4.4.7, 29 Dec 2003):

segfault
 n.,vi.

    Syn. segment, segmentation fault.


The Free On-line Dictionary of Computing (30 December 2018):

segmentation fault
segfault

   An error in which a running Unix program attempts to access
   memory not allocated to it and terminates with a segmentation
   violation error and usually a core dump.

   [Jargon File]

   (1994-12-15)