Related Clues:

• Little shaver
• Sometimes it gets smashed
• Young fellow
• Proton's place
• Cyclotron bit
• Source of nuclear energy
• Slight bit
• Nuclear energy source
• Smallest amount
• Smallest bit
• With 60-Across, 1960's TV cartoon hero
• Slightest trace
• Smashing subject
• Unit of a molecule
• Basic building block