(NO) [adjective] [before noun; not gradable] [informal] - very little or none"Perhaps they'll invite you." "Fat chance of that!"A fat lot of use you are (= You are not useful in any way)!He knows how much trouble it causes, but a fat lot he cares (= he doesn't care).
FAT
Meaning of FAT in English
Cambridge English vocab. Кембриджский английский словарь. 2012