Ballpark, in the ballpark, ballpark figure, and out of the ballpark — "Ballpark" has been used to mean a broad area of approximation or similarity, or a range within which comparison is possible; this usage the Oxford English Dictionary dates to 1960. Another meaning, "sphere of activity or influence", is cited in 1963. "In the (right) ballpark", meaning "within reasonable bounds" dates to 1968. A "ballpark figure" or "ballpark estimate", one that is reasonably accurate, dates to at least 1957. The meaning of "out of the ball park" is to hit a home run; its non-baseball equivalent is to do something well or exactly as it should be done.
