FAC

from The Collaborative International Dictionary of English v.0.48

Fac \Fac\ (f[a^]k), n. [Abbrev. of facsimile.]
   A large ornamental letter used, esp. by the early printers,
   at the commencement of the chapters and other divisions of a
   book. --Brande & C.
   [1913 Webster]

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

FAC

   Functional Array Calculator.  An {APL}-like language, but
   {purely functional} and {lazy}.  It allows infinite {arrays}.

   ["FAC: A Functional APL Language", H.-C. Tu and A.J. Perlis,
   IEEE Trans Soft Eng 3(1):36-45 (Jan 1986)].

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

FAC
       Final Assembly Code (IMEI, GSM, mobile-systems)

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