Possible Clues:

• Group or set of nine
• Supreme Court justices, e.g
• The planets in our solar system, once
• Any promotion reported to be needed for group of nine?
• Term derived from Greek for a set of nine things
• Group or series of nine
• Greek-based word describing groups like the Muses
• The Muses, e.g
• The Supreme Court, e.g
• In the end Ena gets to nine