British slang for an overweight person. This can also be used when describing a swell to the face. Is often used as an insult. Most probably derives from the puffer fish 'Bloat' from finding nemo. Then again, probably not.
Man- Dude, look at him - he's piled on the pounds.
Man- Yeah, what a bloaterface.
Woman1- I ate some shellfish and now I have a bloaterface.
Woman2- You had a bloaterface anyway you fat cow.