A Fresnel zone plate.

(military) An area, often on a border between military factions, in which military forces and operations are prohibited.

(US, California) An area of a street where the curb has been painted white, indicating that the spot is only to be used for the immediate loading or unloading of passengers, baggage or freight, or for short-term parking, and (in some places, such as airports) that a vehicle is not to be left unattended.

An area of a street or a parking lot designated for the loading or unloading of passengers, baggage or freight, or short-term parking for that purpose.

A geographic area in which some sanctioning authority prohibits specific activities, see also Restricted Area.

A structural feature of an automobile/motor car designed to compress during an accident and absorb impact energy.

(American football) A zone between the defensive line of scrimmage and the offensive line of scrimmage.

zone melting

(physics, chemistry) A technique used to purify a metal, semiconductor or other solid in which a heating system slowly causes a series of molten zones to traverse the solid, leaving purer material behind it.

(baseball) The area through which if a pitched ball passes, it will be called a strike, typically from the batter's knees to the belt and the width of home plate.