Gwan is a Pattwa' word, It is mainly a Jamaican term. It can mean two things to *go away or *what is going on
Go away - "Tell da boys dem fi gwan."
what is going on? - "Whatta gwan?"
slang from Cork city in Ireland - short for "go on". The term made it's made to the Carribean while Irish slaves were shipped there in the 16th and 17th centuries. Slang Irish terms like this then made their way into the Carribean "patois", particularly Jamaica, where "gwan" is pronounced and used in exactly the same way as in Cork city in Ireland.
"Ah gwan ya langball ya"
"Please do go on about that wonderful event that you are informing me about."
Alternative for "happening", often used when expressing confusion.
What the fuck is gwanning right now?
A drug dealers word for..
Weed,Marijuana,Cannabis
''yo man can ya get me some gwan?''
..
''Safe yo!,meet ya behind the bike shed after school''