Related Clues:

• Cool, retro-style
• Impressive, to surfers
• Supercool
• ''Swell!''
• Nifty in the '50s
• Bitchin'
• "That's awesome!"
• ''Outta sight!''
• 44-Across, updated
• 'So cool!'
• Eng. cooler
• Old slangy word of enthusiasm
• "Excellent!"
• Remark of approval
• X-ray dose unit