Irix

from The Free On-line Dictionary of Computing (8 July 2008)
IRIX

   <operating system> /ir'iks/ The main {operating system} used
   by {Silicon Graphics} {workstations} and {servers}.  IRIX is
   {multiprocessor} and {multi-threaded}.  It incorporates
   substantial functionality from {UNIX} {System V}, Release 4.1
   and 4.2.

   (1997-06-17)
    

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