godan verb (-tsu)
stand on tiptoe
Describes standing with the heels raised, often to reach something or move quietly.
背が低いので、爪立って棚の上の物を取った。
Being short, I stood on tiptoe to get something from the top shelf.
赤ちゃんが寝ているので、爪
Since the baby was sleeping, I tiptoed out of the room.