[du.plex] adj [L, fr. duo two + -plex -fold--more at two, -fold] (1567) 1 a: having two principal elements or parts: double, twofold b: having complementary polynucleotide strands "~ DNA"
2: allowing telecommunication in opposite directions simultaneously
[2]duplex vt (1833): to make duplex [3]duplex n (1922): something duplex: as a: a 2-family house b: duplex apartment c: a duplex molecule of DNA or of RNA and DNA