security zone

grid zone / grid-zone

zone standard time (zone time) (ZST)

killing zone / kill zone

grid zone designation / Grid Zone Designator

grey-zone / grey zone (international relations)

hundred-per-cent zone (one-hundred-per-cent zone)

no-fire zone / no fire zone

flight restriction zone / flight restricted zone (FRZ)

forefield; foreground; security zone; no man's land

zone of security

closed security zone

security agreement (information security, NATO)

air defense zone

air defense zone commander

air exclusion zone

area of separation (=buffer zone)

assault dropping zone

buffer zone / area of separation

cold zone (CBRN)

combat zone

communications zone (COMMZ)

contact zone

contaminated zone

contamination zone

defense zone

demilitarized zone (DMZ)

detection zone

drop zone (DZ)

engagement zone

exclusion zone

fighter engagement zone (FEZ)

free fire zone