from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Slang A phenomenon, especially a remarkable or outstanding person.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Someone or something that is phenomenal, especially a young player in sports like baseball, American football, basketball, tennis, and golf
- n. One who is hip and fashionable
From phenomenon ("remarkable occurrence") by shortening. First use in United States around 1890s. (Wiktionary)