Related Clues:

• ''Nifty!''
• Like, totally bitchin'
• 'Impressive, dude!'
• 'Peachy keen!'
• Dated expression of appreciation
• "Swell"
• "In the old grooveroo"
• Like many a 21-Down
• Up on things, daddy-o
• Cool, as a daddy-o
• Car part, slangily
• 'Way cool, man!'
• Badass
• Mr. Dithers, to Dagwood
• Old-fashioned "cool"