WordNet (r) 3.0 (2006):

telecommunication
    n 1: (often plural) systems used in transmitting messages over a
         distance electronically [syn: telecommunication,
         telecom]
    2: (often plural) the branch of electrical engineering concerned
       with the technology of electronic communication at a distance

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "telecommunication":
   communication engineering, communication explosion,
   communication technology, communication theory, communications,
   communications engineer, communications industry,
   communications medium, communications network,
   electrical communication, electronic communication,
   electronic communications, information explosion,
   information theory, media, radio, radiocommunication,
   radiotelegraphy, radiotelephony, signaling, wire communication,
   wireless, wireless communication