quadruplex adjective 3noun 2verb 1forms 3 adjective3 •Having four components. •Of or relating to a system in telegraphy by which four messages (two in each direction) can be sent on one wire simultaneously. •Of or relating to an early videotape format with four magnetic record/reproduce heads mounted on a headwheel spinning transversely across the tape. noun2 •A quadruplex system. •Clipping of quadruplex videotape, an early type of videotape with four magnetic record/reproduce heads mounted on a headwheel spinning transversely across the tape. verb1 •To make quadruplex. formsquadruplexed · quadruplexing · quadruplexes