Related Clues:

• "Groovy!"
• "Cool, dude!"
• "Coolio!"
• "Keen!"
• Retro ''Way cool!''
• "How nifty!"
• 'How nifty!'
• Geiger counter unit
• The earliest known printing of this US slang term for “excellent” was in 1951
• "Groovy," in the '80s
• "How cool"
• Trigonometry meas
• “Far out!” in dated slang
• Unit akin to the roentgen
• Incredible person, slangily