INTERCOM

n. intercommunication system; internal two-way communication system

An intercom (intercommunication device) is an electronic communications system within a building or group of buildings. Intercoms are generally composed of fixed microphone/speaker units which connect to a central control panel. A small home intercom might connect a few rooms in a house. Larger systems might connect all of the rooms in a school or hospital to a central office. Intercoms in larger buildings often function as public address systems, capable of broadcasting announcements.
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Noun
1. a communication system linking different rooms within a building or ship etc
(synonym) intercommunication system
(hypernym) communication system
(hyponym) interphone
(part-meronym) squawk box, squawker, intercom speaker

n. intercom, intercommunication system; internal two-way communication system

1. A telephone apparatus by means of which personnel can talk to each other within an aircraft, tank, ship, or activity. [JP1] 2. A dedicated voice service within a specified user environment. (188 )