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rough (estimate, summary, etc.); broad; general; sweeping; loose
careless (e.g. work); sloppy; crude
大雑把な計画のままでは失敗しやすい。
Rough plans tend to fail.
彼女は大雑把な性格で知られているね。
She is known for her rough personality.
大雑把に言えばそういうことになります。
Roughly speaking, that's how it is.