From Longman Dictionary of Contemporary Englishtell me about ittell me about itKNOW somethingused to say that you already know how bad something is, especially because you have experienced it yourself ‘I’ve been so tired lately.’ ‘Yeah, tell me about it!’ → tell
Examples from the Corpus
tell me about it• "I'm totally sick of my boss." "Yeah, tell me about it."• Can you tell me about it?• I remember the day when they told me about it.• She had had a rewarding session with the dressmaker and wanted to tell me about it.• You got problems, man, you tell me about it.• Her father, Meir Ahronson, told me about it himself.• But I was pleased they had told me about it once. 