posix

from The Free On-line Dictionary of Computing (8 July 2008)
Portable Operating System Interface
POSIX

   <operating system, standard> (POSIX) A set of {IEEE} standards
   designed to provide {application} {portability} between {Unix}
   variants.  IEEE 1003.1 defines a Unix-like operating system
   interface, IEEE 1003.2 defines the {shell} and utilities and
   IEEE 1003.4 defines {real-time} extensions.

   ["More UNIX For Dummies", ISBN: 1-56884-361-5] says it stands
   for "Portable Operating System Interface with an X thrown in
   to make it sound cooler."

   (1997-12-04)
    
from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)
POSIX
       Portable Operating System for unIX (OS, IEEE 1003, ISO 9945,
PASC, Unix)
       
    

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