n. (美)棒球场;活动领域;可变通范围
adj. 大约的
The result, according to the author's estimate, is a stockpile equivalent to one billion tons of TNT. Assuming this estimate is "in the ball park," clearly there is valid reason for urging candor on the part of our government. [Ralph E. Lapp, "Atomic Candor," in "Bulletin of the Atomic Scientists," October 1954]