A term used for a person who is so attractive or 'fine' that interacting with them causes others to behave in a 'dumb' fashion. Such 'dumb' behavior can include stammering, stuttering, saying and doing unintentionally embarrassing things, and generally acting a fool.
On a diamond mine grind, she was dumb fine
But not quite the type that you might want to wine and dine
Madvillain - Great Day