Source : WordNet®

FM
     n 1: modulation of the frequency of the (radio) carrier wave
          [syn: {frequency modulation}]
     2: a radioactive transuranic metallic element produced by
        bombarding plutonium with neutrons [syn: {fermium}, {atomic
        number 100}]

Source : Free On-Line Dictionary of Computing

FM
     
        1.  {Frequency Modulation}.
     
        2.  Fucking Manual, a back-formation from {RTFM}.
        Used to refer to the manual itself.
     
        3.  Fucking Magic, in the sense of {black magic}.
     
        (2001-04-30)

fm
     
         The {country code} for the Federated States of
        Micronesia.
     
        Heavily used for {vanity domains} by FM radio stations.
     
        (1999-01-27)