Related Clues:

• Innocent's claim
• "Not gonna happen"
• Polite turndown
• 'Fat chance'
• "I don't think so"
• Curt turndown
• 'Don't think so!'
• Opposite of 15-Across
• "Don't think so"
• Polite denial
• 'Unh-unh'
• "I don't think so!"
• No, informally
• 'Don't look at me'
• 'Ixnay'