Adam Jones, the Wales and Lions prop, was reported as saying about his policy regarding the referee before yesterday's match:-
You have to get the ref on the right side of you. You don't want to be in their face, chopsing at them, getting on their nerves and pissing them off...
Chopsing is a new word to me. Looking it up, the only definition I can find is on the Urban Dictionary:-
'Chopsing' is a Welsh slang term for arguing or saying disrespectful things to someone.
This seems quite an apposite definition, and works well given the context, but is there a more reliable source for this word? Are there any clues as to the etymology?