The term "gnarly" originally described something that was twisted or knotted, often used in reference to tree branches. Over time, it evolved in slang to mean something that is impressive, exciting, or awesome, particularly in surf culture. It conveys a sense of admiration for something that is extreme or challenging. In contemporary usage, "gnarly" is often associated with extreme sports, such as skateboarding or snowboarding, where athletes push their limits. It can also describe thrilling experiences or remarkable achievements, making it a versatile term in casual conversation among younger generations.