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exactly; precisely; punctually; on the dot
closely; tightly; (fitting) perfectly
properly; without fail
きっちり計算して一円も誤差がなかった。
I calculated precisely with no margin of error.
荷物をきっちり詰めてスペースを有効活用した。
I packed the luggage tightly and made good use of space.
彼はきっちり時間通りに来る人として知られる。
He's known as someone who comes exactly on time.