Related Clues:

• Stop!
• Terse bit of advice
• Terminate
• Sufficiently
• "Stop it!"
• It's followed by "Who goes there?"
• "Freeze!"
• Pause
• 'Uncle!'
• Admonisher's word
• Guard's shout
• Terse warning
• 'I'd advise against it'
• Marching order
• Parent's warning