PBX

n. telephone system that is owned by an organization (in which each worker has a line for internal calls while sharing a few external lines with the other workers)

A Private Branch eXchange (PBX) is a telephone exchange that serves a particular business or office, as opposed to one that a common carrier or telephone company operates for many businesses or for the general public. PBXs are also referred to as:PABX - Private Automatic Branch eXchangeEPABX - Electronic Private Automatic Branch eXchange
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Abbreviation for private branch exchange. 1. A subscriber-owned telecommunications exchange that usually includes access to the public switched network. 2. A switch that serves a selected group of users and that is subordinate to a switch at a higher level military establishment. (188 ) 3. A private telephone switchboard that provides on-premises dial service and may provide connections to local and trunked communications networks. (188 ) Note 1: A PBX operates with only a manual switchboard; a private automatic exchange (PAX) does not have a switchboard, a private automatic branch exchange (PABX) may or may not have a switchboard. Note 2: Use of the term "PBX" is far more common than "PABX," regardless of automation.

See PBX.

Private Branch Exchange

Private Branch Exchange - a telephony term describing a private telephone network used within an enterprise. Users of the PBX share a certain number of outside lines for making external telephone calls.

Context: Infotech