IOS

from The Collaborative International Dictionary of English v.0.48

Io \I"o\, n.; pl. {Ios}. [L.; cf. Gr. "iw`.]
   An exclamation of joy or triumph; -- often interjectional.
   [1913 Webster]

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

IOS

   {Internetworking Operating System}

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

IOS
       Internetworking Operating System (Cisco, OS)

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

IOS
       InterOrganizational Systems

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