os2

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

OS2

   <spelling> Normally written "{OS/2}".

   [{Jargon File}]

   (1997-05-02)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

OS2
       Operating System /2 (IBM, OS), "OS/2"

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