BFO

BFO - Big Feck-Off, meaning very large. Also may inclde Great Feck-Off (GFO) or Great Big Feck-Off (GBFO).

Normal usage would be in the phrase Big Feck Off Gun or a Big Feck Off Knife...

An example would be from the movie Crocodile Dundee when the hero is menaced by a Michael Jackson like chav with a flick knife...

"Thats not a knife ... <pulls out Golok> ... Now THATS a knife!"

Find out more in the Dictionary