The Free On-line Dictionary of Computing (19 January 2023):

SuperZap

    An IBM utility program used to quickly patch
operating
   system or application program executable code or disk VTOCs in
   preference to editing the source code and recompiling.  SuperZap
could write
   data given as a string of hex digits to a given disk location in a
matter of
   seconds.

   The SuperZAP program was a quick hack written by one IBM
   Engineer, possibly from IBM UK, in the late 1960s to directly
   fix executable files.  He needed to fix a bug but it would
   have taken hours to rebuild the vast OS/360 executables.

   Soon the IBM development labs were releasing all Programming
   Temporary Fixes (PTFs) to OS/360 in this form.  OS/360
   included a version called IMASPZAP or AMASPZAP which persisted
   through MVS, MVS/SP, MVS/XA, OS/390 and probably still
   remains in z/OS, the distant descendent of OS/360.

   The program name owed less to its use of the Zero and Add Packed
(ZAP)
   instruction and more to SF films in which aliens were zapped with
lasers.

   [2004-02-05 e-mail from Chris Gage and 2015-01-03 email
   from Ray Saunders, both IBM employees and SuperZap users].

   (2021-03-21)