/kwod'reuh fon"ik/ , adj.
of, noting, or pertaining to the recording and reproduction of sound over four separate transmission or direct reproduction channels instead of the customary two of the stereo system: a quadraphonic recording.
Also, four-channel, quadriphonic, quadrasonic /kwod'reuh son"ik/ . Cf. monophonic, stereophonic .
[ 1965-70; quadra-, var. of QUADRI- + -phonic, as in STEREOPHONIC ]