Sunos

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

   <operating system> {Sun Microsystems}' version of {Unix} for
   Sun {workstations}.  SunOS is similar to {BSD Unix} with some
   {SVR4} features and {OpenWindows} 3.0.

   After version 4, SunOS was integrated into Sun's {Solaris}
   "operating environment".

   (1999-03-26)
    
from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)
SUNOS
       SUN Operating System (Sun, OS, SPARC), "SunOS"
       
    

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