designating or of a form of radio reception in which part of the amplification prior to demodulation is carried out at an intermediate supersonic frequency produced by beating the frequency of the received carrier waves with that of locally generated oscillations
super(sonic) + heterodyne
a radio set for this method of reception
See superheterodyne in American Heritage Dictionary 4
Of, relating to, or being a form of radio reception in which the frequency of an incoming radio signal is mixed with a locally generated signal and converted to an intermediate frequency in order to facilitate amplification and the rejection of unwanted signals.