(1)a very short time (as the time it takes the eye to blink or the heart to beat); "if I had the chance I'd do it in a flash"
(2)非常に短い時間（瞬きするは心臓が鼓動する間ほどの）
(3)a reflex that closes and opens the eyes rapidly
(4)目をすばやく閉じたり開けたりする反射作用