- The definition of white-knuckle is something tense or something that causes fear and apprehension.
When an airplane has to make an emergency landing which caused extreme nervousness for the flight crew and passengers, this is an example of a white-knuckle landing.
Origin: from the appearance of a hand clenched inch(es) fear
Used by arrangement with John Wiley & Sons, Inc.
also white-knuck·ledadjective Slang