[] the central part of a telephone system used by a company, etc., where telephone calls are answered and connected (put through) to the appropriate person or department; the people who work this equipment （电话的）交换机，交换台，总机；总机话务员◆a switchboard operator 交换台接线员◆Call the switchboard and ask for extension 410. 先打电话给总机，然後要求转分机 410.