traditionally an Australian expression,varying the tone when spoken these two words can take on many different meanings
1. To get attention.
"oi cunt!" Johnny shouted to his mate Screwy who was on the other end of the piss-trough
2. To get someones attention and direct it 2 somewhwere else.
"oi cunt.." Johnny wispered to Screwy, eye signalling in the direction of the chooney
thats about to walk past the new high-tech-see-thru-glass piss trough
"oi cunt.." said Johnny pointing to his oblivious mate,Screwy, whose foot was now in the piss trough
3. To draw attention to the seriousness nature of a conversation and project authority. generally in a 'speaking down to them' manner, esp. used after been spoken down to yourslef
taxi driver: "ure still 30 cents short"
old racist man: "oi cunt..i used 2 break little peoples legs like yours bak in 'nam
taxi driver: "go fuck yourself, fucken..ill fuck you up. wheres my fucken 30 cents?!?
Random cunt at the pub pointing to Robbo: "Whose this cunt?"
Robbo: "Oi cunt, call me a cunt
again and ill fuck your arse
till my cock falls off
Random cunt at the pub: im sorry it wont happen again..