Special Flight Rules Area (SFRA)

An area in the NAS, described in 14 CFR Part 93, wherein the flight of aircraft is subject to specialtraffic rules, unless otherwise authorized by air traffic control. Not all areas listed in 14 CFR Part 93 are designated SFRA, but Special Air Traffic Rules apply to all areas described in 14 CFR Part 93.

Source: Pilot Contoller Glossary (PCG)