startle

From Middle English startlen, stertlen, stertyllen (“to rush, stumble along”), from Old English steartlian (“to kick with the foot, struggle, stumble”), equivalent to start + -le. Cognate with Old Norse stirtla (“to hobble, stagger”), Icelandic stirtla (“to straighten up, erect”). Compare also Middle English stertil (“hasty”). More at start.