Related Clues:

• What's up?
• Back from dreamland
• Vigilant
• Not out
• Burning the midnight oil
• On one's toes
• Cognizant
• Opposite of 'out'
• Up and at 'em
• Not sleeping
• Out of the sack
• Not in dreamland
• Stop sleeping
• Hardly oblivious
• Bright-eyed and bushy-tailed