Wiktionary
white-knuckle ride
alt. 1 An extremely exciting ride at an amusement park, etc., where one's hands grip on so tightly that the knuckles appear white. 2 (context figuratively English) Any extremely exciting or nerve-wracking experience. n. 1 An extremely exciting ride at an amusement park, etc., where one's hands grip on so tightly that the knuckles appear white. 2 (context figuratively English) Any extremely exciting or nerve-wracking experience.