1.  combat zone(n = noun.location) tenderloin - a city district known for its vice and high crime rate;
is a kind of city district

2.  combat zone(n = noun.location) combat area - a military area where combat forces operate;
is a kind of zone
is a part of field, field of operations, theater, theater of operations, theatre, theatre of operations
has particulars: war zone, bridgehead, foothold

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