Dictionary
quad•ru•plex
Pronunciation: (kwod'roo-pleks", kwo-drOO'pleks), [key]—
adj.
1. fourfold; quadruple.
2. noting or pertaining to a system of telegraphy by which four messages may be transmitted simultaneously over one wire or communications channel.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.