diplex

[dahy-pleks]

adjective

pertaining to the simultaneous operation of two radio transmitters or to the simultaneous reception and transmission of radio signals over a single antenna through the use of two frequencies.

Origin of diplex

First recorded in 1875–80; di-¹ + -plex

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Diplex, dī′pleks, adj. pertaining to the transmission of two simultaneous messages over one wire in the same direction.
Chambers's Twentieth Century Dictionary (part 1 of 4: A-D)
Various

diplex in Science

[dī′plĕks′]

Capable of simultaneous transmission or reception of two electronic or radio signals through a single channel or component, as the simultaneous transmission of two radio signals through a single antenna.