What is Fo'sh?
1.
Basic meaning is "definitely". Shortening of the term "for sure".
Typically used when genuinely excited, so usually accompanied by an exclamation mark.
Originated in early 2009 within the pseudo-indie-bizzaro-trendy scene in Perth, Australia.
Note on pronunciation:
"Fow-sh", where "fow" is like in "bow and arrow", not "fosh".
"Are we on for tonight?"
"Fo'sh!"
See 
Random Words:
1. 
(also written as ungooglable) 
adj. 1) failing to return results from a search engine, especially google. 
2) effectively anonymous in..