Air Route Traffic Control Center - a "long-distance" ATC facility, known more briefly as "Center"

Air Route Traffic Control Center. A facility that provides air traffic control service to aircraft operating on an IFR flight plan within controlled airspace.

Air Route Traffic Control Center. A facility established to provide air traffic control service to aircraft operating on IFR flight plans within controlled airspace and principally during the en route phase of flight. When equipment capabilities and controller workload permit, certain advisory/assistance services may be provided to VFR aircraft. There are 20 ARTCCs in the continental U.S.