Related Clues:

• Fireworks watcher's word
• '90125' band
• Proposal response, often
• "That's an affirmative"
• 'Sounds good!'
• Thumbs-up answer
• Sound from a wowed crowd
• 'I'd be glad to!'
• "I like!"
• "Definitely!"
• "Indubitably!"
• "Affirmative"
• 'So nice!'
• What 40-Across means
• Unveiling response, perhaps