VSE

from The Free On-line Dictionary of Computing (8 July 2008)
Virtual Storage Extended
VSE

   <operating system> (VSE, formerly DOS/VSE) is a
   {multitasking}, {IBM 370}-architected {operating system}
   similar to {Multiple Virtual Storage} (MVS).

   VSE run jobs in {partitions} rather than {address spaces}, and
   uses {POWER} for input/output rather than {JES}, but is
   largely similar to MVS.  Subsequent VSE/{ESA} releases gave
   VSE the {XA-370} channel architecture, 31-bit virtual and real
   storage support, and data spaces.  VSE is the {IBM} operating
   system on one-third of installed {IBM 4381s} and a significant
   proportion of {IBM 9370s} as well.  It offers {transaction
   processing} and {batch processing} capabilities well beyond
   {Virtual Machine}'s current capabilities, and has a close
   affinity with MVS.

   (1997-06-09)