Definition: GCHQ

(Government Communications HeadQuarters) The 100-year-old U.K. organization responsible for intelligence and security. The GCHQ was established in 1919 as the Government Code and Cypher School (GC&CS), which was renamed GCHQ in 1946. The National Cyber Security Center (NCSC) falls under the GCHQ's jurisdiction. Counter terrorism, cyber security and fighting organized crime are top priorities of the agency.