full duplex
 全雙工 FDX
 Du·plex a.
 1. Double; twofold.
 Duplex escapement, a peculiar kind of watch escapement, in which the scape-wheel has two sets of teeth. See Escapement.
 Duplex lathe, one for turning off, screwing, and surfacing, by means of two cutting tools, on opposite sides of the piece operated upon.
 Duplex pumping engine, a steam pump in which two steam cylinders are placed side by side, one operating the valves of the other.
 Duplex querela [L., double complaint] Eccl. Law, a complaint in the nature of an appeal from the ordinary to his immediate superior, as from a bishop to an archbishop. --Mozley & W.
 Duplex telegraphy, a system of telegraphy for sending two messages over the same wire simultaneously.
 Duplex watch, one with a duplex escapement.
 half duplex Computers (a) arranged so that the information may be transmitted in both directions, but only in one direction at a time; -- of communications channels between computers; contrasted with full duplex(a).  (b) arranged so that the information transmitted to the remote computer also appears on the local terminal; -- of communications channels between computers; contrasted with full duplex(b).
 full duplex, Computers (a) arranged so that the information may be transmitted in both directions simultaneously; -- of communications channels between computers; contrasted with half duplex(a).  (b) arranged so that the information transmitted to the remote computer does not appear on the local terminal; -- of communications channels between computers; contrasted with half duplex(b).