Related Clues:

• See 19 Across
• Defiant exclamation
• "That'll show you!"
• ''Don't hold your breath!''
• On the 31st of February
• "As if!"
• Scoffer's cry
• ''Not a chance!''
• Taunting laugh
• 'No way, no how!'
• ''That's a laugh!''
• 'Not on your life!'
• "Oh, sure!"
• ''Told you!''
• 'When hell freezes over'