Related Clues:

• Source of inspiration
• Mull
• Erato is one
• Calliope, for one
• Artist's "visitor"
• 23-Down is one
• Clio, Erato or Urania
• Clio, Erato or Urania, e.g.
• Ruminate
• Melpomene, e.g.
• Meditate over
• Writer's inspiration
• There's one for dance
• Be introspective
• Urania, e.g.