機敏さ

(1)a rate (usually rapid) at which something happens; "the project advanced with gratifying speed"

(2)何かが起こる（通常は敏速な）速さ

(3)skillful performance or ability without difficulty; "his quick adeptness was a product of good design"; "he was famous for his facility as an archer"

(4)問題のない巧みな演奏、または能力

(1)