from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Slang Excellent; first-rate: phat fashion; a phat rapper.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. excellent
- adj. sexy
- adj. rich in texture, prominent
Earlier, sexy (said of a woman), of unknown origin.(American Heritage® Dictionary of the English Language, Fourth Edition)
The term derives from African American Vernacular English as a deliberate misspelling of the word fat. (Wiktionary)