Related Clues:

• Top-notch, in slang
• Smashing
• ''Awesome!''
• '90s kids' shout
• 'Groovy!', updated
• "Cool!"
• 'Far out, man!'
• Socko
• First-class, in slang
• "Incredible!"
• ''Peachy keen!''
• Swell, to surfers
• ''Fabulous!''
• Radioactivity unit
• "So cool!"