Source : WordNet®

amplitude modulation
     n : modulation of the amplitude of the (radio) carrier wave
         [syn: {AM}]

Source : Free On-Line Dictionary of Computing

Amplitude Modulation
     
         (AM) A method of encoding {data} by varying
        the {amplitude} of a constant {frequency} {carrier}.
     
        Contrast {Frequency Modulation}.
     
        (2001-04-30)