Source : Webster's Revised Unabridged Dictionary (1913)

Mos \Mos\, n.,
   sing. of {Mores}.

Mores \Mo"res\ (m[=o]"r[=e]z), n. pl.; sing. {Mos} (m[=o]s).
   [L.]
   Customs; habits; esp., customs conformity to which is more or
   less obligatory; customary law.

Source : Free On-Line Dictionary of Computing

MOS
     
        {Metal Oxide Semiconductor}