Related Clues:

• Chess opening?
• Circled letter, often
• Comic's beginning or end?
• Greenhouse growth
• Oxygen producer
• 2.0 equivalent
• O.K. mark
• Botanist's study
• Flower or weed
• Choir leader?
• Covert agent
• It's soft in ''Cinderella''
• Start to crumble?
• ''Jay'' or ''em'' attachment
• Carnival shill, e.g.