Possible Clues:

• "What's the ___?"
• "What's the __?": "So what?"
• “What’s the ___?”
• Distinction, briefly
• "What's the __?": "Seems the same to me"
• Distinction, slangily
• Distinction: Abbr.
• "What's the ---?"
• 'What's the ___?' ('So what?')
• 'What's the --?' ('So?')