Related Clues:

• Word with red or on
• Observant
• Eye-opener?
• Fill with fear
• Clock radio feature
• Red state?
• Like a worthy watchdog
• It's a real eye-opener
• Antitheft device
• Having heightened senses
• Wake-up call
• APB, for one
• Clock-radio feature
• Morning surprise, often
• A serious one may be red