(
Canadian usage)
1)To be verbally insolent,
belligerent or insubordinate;
2)To be mouthy to or backtalk someone;
3)To
complain profusely about something.
"I'd love to
dig a new trench, Sergeant. And if I thought you knew what you were
talking about, I might do it."
"Are you beaking off, Corporal?"
"He's still beaking off about losing the election, and that was
six months ago!"