Related Clues:

• ''I don't think so''
• Terse refusal
• "Not gonna happen"
• 'Fat chance'
• "I don't think so"
• "Ixnay"
• Curt turndown
• "Nope"
• 'Don't think so!'
• Opposite of 15-Across
• "No way!"
• "Don't think so"
• 'Unh-unh'
• "I don't think so!"
• No, informally