Source : WordNet®

megahertz
     n : one million periods per second [syn: {MHz}, {megacycle per
         second}, {megacycle}, {Mc}]

Source : Free On-Line Dictionary of Computing

MegaHertz
     
        (MHz) Millions of cycles per second.  The unit of frequency
        used to measure the {clock rate} of modern digital logic,
        including {microprocessor}s.
     
        (1994-10-27)