Quadruplex
Pronunciation : Quad"ru*plex
Part of Speech : a.
Etymology : [L., from quattuor four + plicare to fold.]
Definition : Defn: Fourfold; folded or doubled twice. Quadruplex system (Electric Telegraph), a system by which four messages, two in each direction, may be sent simultaneously over the wire.
Source : Webster's Unabridged Dictionary, 1913