Since it is the impact point for the bomb, it is, of course, the point of highest damage. Around that spot are drawn concentric circles showing how far out from the impact point the circle is.
The term has chiefly come to be associated with nuclear explosions, but is also used for earthquakes, epidemics and other disasters.
It was military slang used at the Trinity site where the weapon tower was at point 'zero' and moved into general use very shortly after the end of World War II (see nuclear weapons).
Western journalists—ever eager to label subjects with short, catchy terms—applied the term to describe the former site of the World Trade Center, which was destroyed in the September 11, 2001 terrorist attacks. Rescue workers at the site of the collapse avoided this term as insensitive, disrepectful, even offensive, to those that died. The phrase "The Pile", as in the pile of rubble that was left after the buildings collapsed, was the term used by the rescue workers themselves. See World Trade Center site for reconstruction news.
The term is also apparently used by members of the U.S. armed forces to describe the open space at the center of The Pentagon, in a blackly humorous reference to the likelihood of its being a nuclear weapons target in any nuclear war.
There is also a film named Ground Zero. This film is about a documentary filmer who gets into trouble after filming at a site in Australia used by Great Britain for nuclear tests using aboriginal population as guinea pigs,World Trade Center
Other uses