A person in the Oi music scene who isnt necissarily a skinhead.
There were some Oi Boys at the Rudimentary Peni show.
Can be used as anything. To capture someone's attention, to exclaim either positively or negatively regarding anything, a greeting, a farewell, a wake-up call... Anything.
James: Ben, can you see those sexi gurlz down there?
Ben: Yes, yes I can. (At girls) OI BOY.