Related Clues:

• Sound in the head
• Lucid
• 'Fantastic!'
• Unflappable
• Has enough marbles
• Right-minded
• Nifty
• Playing will a full deck, so to speak
• Capable of thinking clearly
• ''Neato!''
• See 68-Across
• Not out of one's mind
• Clear-headed
• The Hollies' ''Long --- Woman''
• End of the comment