立たちすくむ

godan verb (-mu), intransitive verb

stand frozen; be petrified; be paralyzed with fear or shock

Describes being so shocked, scared, or amazed that one cannot move; often used with emotions like horror, surprise, or awe.

• 突とつ然ぜんの大おおきな音おとに、彼かれはその場ばに立たちすくんだ。

  He stood frozen on the spot at the sudden loud noise.

• あまりの光こう景けいに、私わたしは言こと葉ばもなく立たちすくんでいた。

  I was standing there speechless, petrified by the sight.