Related Clues:

• Fluorescence
• See 17 Across
• Radiant quality
• Have an aura
• Glisten
• Gentle firelight, e.g.
• Shine softly
• Light from a lightning bug, e.g.
• U.F.O. feature, maybe
• Give off light
• Neon effect
• Gleam
• Be visibly happy
• Radiate light
• Look healthy