a. 四倍的, 四重的, 四路多工的, 四重信号的

[计] 四工系统

[ adj ]
having four units or components
<adj.all>
quadruple rhythm has four beats per measurequadruplex wire

Quadruplex \Quad"ru*plex\, a. [L., from quattuor four + plicare
to fold.]
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.