Pronunciation: (hwīt'nuk'ul, wīt'-), [key]
1. causing fear, apprehension, or panic: The plane made a white-knuckle approach to the fogged-in airport.
2. experiencing fear, terror, or apprehension: The white-knuckle crowd loved that director's newest horror movie. Also,white'-knuck'led.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.