du·plex (dplĕks′, dy-)
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.
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.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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