1
what you say when you're too lazy to listen, don't care what they're saying, or you're just plain dumb and don't know what they're talking about. It's like a conversation ender and a insult all in one.
'I know what that's about!' said Jake as he walked out of the room, clearly not listening to a word I said.
'I know what that's about!' shouted Mike when I told him I got a B on the test.
'I know what that's about!' yelled Sarah when I asked her why she was crying.