From Longman Dictionary of Contemporary Englishso what?so what? (also what of it?) used to say that you do not care about something or think it is important ‘Your room looks a real mess, Tracey.’ ‘So what?’ ‘But, Paul, she’s so much older than you.’ ‘What of it?’ → what
Examples from the Corpus
so what?• "Don't go in there, he's sleeping." "So what?"• She might think he was a little coarse doing that after saying he despised her, but so what?• We are behind in the opinion polls. So what?• You climbed Mount Everest? So what?• After all, Twickenham only holds 65,000 people, so what about the other fans throughout the country?• And the special language of the specialist is a substitute for thought. So what are we to do?• Part of the fun includes a trip to make-up. So what does the future hold for Fiona and David?• And so what, she thought, so what?