adj. 1. Twofold; double. 2. Having two apartments, divisions, or floors. 3. Relating to or being a single assembly of machinery having two identical units that are capable of operating simultaneously or independently. 4. Electronics Of or relating to a communications mode, as in a telephone system, that provides simultaneous transmission and reception in both directions. n. 1. a. A house divided into two living units or residences, usually having separate entrances. b. A duplex apartment. 2. Something, such as a communications system, that is duplex. [Latin; see dwo- in the Appendix of Indo-European roots.] du·plexi·ty (-plĕksĭ-tē) n. |
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