Related Clues:

• 'Hey, stop right there!'
• Horse's halter?
• Steed stopper
• "Hold on!"
• 'Unbelievable!'
• "Take it easy!"
• Cry of surprise
• 'Man!'
• "I'm impressed!"
• "Amazing!"
• "Stop, Silver!"
• Jockey's cry
• 'Slow down!'
• It may stop a runaway
• Amazed exclamation