superheterodyne
adjective
su·per·het·ero·dyne ˌsü-pər-ˈhe-tə-rə-ˌdīn 
-ˈhe-trə-
: used in or being a radio receiver in which an incoming signal is mixed with a locally generated frequency to produce an ultrasonic signal that is then rectified, amplified, and rectified again to reproduce the sound
superheterodyne noun
Word History
Etymology
supersonic + heterodyne
First Known Use
1920, in the meaning defined above