What it means
とっさに describes an action or reaction performed instantly and instinctively, usually in response to sudden danger, surprise, or an unexpected event. It emphasizes that there was little or no time for deliberate thought. It commonly modifies verbs involving physical movement, decisions, speech, or other immediate reactions.
Usage note
とっさに is stronger than simply saying an action happened soon: it suggests a reflexive response under pressure. It is normally used with an action or reaction that can occur immediately, rather than with a planned or gradual activity.
How to use it
彼はとっさに身をかわしました。
He reflexively dodged.
彼はとっさに身をかわした。
He reflexively dodged.
Example sentences
背後で突然大きな音がしたので、とっさに身をかがめた。
Because there was suddenly a loud noise behind me, I crouched down at once.
停車中の車が急に動き出したため、運転手はとっさにブレーキを踏み込んだ。
Because the car that was stopped suddenly began to move, the driver instantly pressed down on the brake.
強風で看板が頭上