contrary to popular belief the term '
fat knacker' is quite often used to insult someone who is not actually
fat. But who is stuffing their amply sized gob full of something a fat person would eat.
Implies that they get knackered whilst eating hence the term
fat knacker.
Also can be used to describe someone who is just insanely
fat and gets tired shuffling to the fridge.
(note: i have absolutely nothing against fat people, the term
fat knacker would only be used (in my case) to describe someone fat and a total ass wipe)
WTF! you're going back for another
hamburger? you better hurry up and eat that then you
fat knacker!
Fat Person: 'Ha! look at that bitch Lucy over there'
Me: Shut the fuck up you
fat knacker!