transmission line, cable, line - a conductor for transmitting electrical or optical signals or electric power

central, telephone exchange, exchange - a workplace that serves as a telecommunications facility where lines from telephones can be connected together to permit communication

communication system - a system for communicating

MEDLINE - the computer-based telephone system of the United States National Library of Medicine that provides rapid linkage to MEDLARS

patchboard, plugboard, switchboard - telephone central where circuits are completed with patchcords

phone, telephone, telephone set - electronic equipment that converts sound into electrical signals that can be transmitted over distances and then converts received signals back into sounds; "I talked to him on the telephone"