Generic term for a coordination centre handling SAR; MRCC is the maritime variant, ARCC the aviation variant.
Regulatory detail & full definition
Many countries operate JRCC (Joint Rescue Coordination Centre) handling both maritime and aviation SAR. Equivalent terminology: 'Rescue Coordination Centre' (US/Canada), 'JRCC' (Australia, Norway, NZ), 'MRCC' (most European). All conform to the SAR Convention 1979 service-coordination framework.