Multiplex - (Multiplexer, Multiplexer-demultiplexer, Encoder, Mux, Muldex) - (1) A telecommunications device that funnels a number of signals onto a single channel; for instance audio, video or enhanced data. (2) A device that converts an analog video signal to a digital video signal using one or more compression techniques.

Multiplexing - A general term for combining types of data and/or signals and sending it to a receiver(s).
Demultiplexer (Demux)