古英語のstille「固定された、動かない」から、原ゲルマン語*stilli「固定された」から、PIE*stel「置く、立つ」から、語源的にはstall「立つ」と同じ。
And he said, Go forth, and stand upon the mount before the LORD. And, behold, the LORD passed by, and a great and strong wind rent the mountains, and brake in pieces the rocks before the LORD; but the LORD was not in the wind: and after the wind an earthquake; but the LORD was not in the earthquake: and after the earthquake a fire; but the LORD was not in the fire: and after the fire a still small voice. [1 Kings 19:11-13]Used as a conjunction from 1722.