1. [syn: quadruple, quadruplicate, quadruplex, fourfold, four-fold]
The Collaborative International Dictionary of English v.0.48:
Quadruplex \Quad"ru*plex\, a. [L., from quattuor four + plicare
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.
WordNet (r) 3.0 (2006):
adj 1: having four units or components; "quadruple rhythm has
four beats per measure"; "quadruplex wire" [syn:
quadruple, quadruplicate, quadruplex, fourfold,
The Free On-line Dictionary of Computing (18 March 2015):
A kind of telegraphy system developed by
Thomas A. Edison in the 1870s combining diplex and duplex
communications to support simultaneous transmission of two
messages in each direction.