Centrex

Centrex is a contraction of central exchange, a kind of telephone exchange.
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Centrex, the common name of the Central Police Training and Development Authority (CPTDA), was established under Part 4 of the Criminal Justice and Police Act 2001, and was the primary means of police training in the United Kingdom. It was based at Bramshill House, formerly known as the Police Staff College, Bramshill. Centrex had the responsibility for many aspects of police training and development. There had been a move away from running Police Training Centres to running Police trainee/initial probationer courses in-house under the auspices of Centrex. Centrex was replaced by the National Policing Improvement Agency (NPIA) on 1 April 2007.
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Noun
1. (CENTRal EXchange) a kind of telephone exchange
(hypernym) central, telephone exchange, exchange

Central office exchange service