How I’ve heard it being used (pre-Guyana)
Mr. A.: How are you?
Mr. B.: I am fine, thank you.
In this case, it means that you’re alright/good/okay.
Mr. C.: Look at that girl. She’s soooo fine! I’m gonna go dance with her.
In this case, he means that the girl is hot/beautiful and all the other flattering words you can say to a girl.
How Guyanese use it
Mr. C.: Look at dat fine girl! She look like a stick!
In this case, it means that the girl is skinny.
If he had said fine three times (“fine fine fine girl”), it means she’s REALLY skinny.
How Samson Learned the Definition
(Samson is a Ugandan volunteer who works with SCPDA in the Aishalton office)
Samson: How are you? Are you fine?
Little boy: NO! I am fat!
It so happens he IS a round little boy! And apparently very self-aware.