Possible Clues:

• 'N -- (pop boy band)
• Coordinate, as a phone and computer
• Agreement in time of Seychelles with North Carolina
• In ___ (working together)
• Fit sound to action, e.g.
• Informal word for unison
• A coinciding or agreement in time
• Match, informally
• Simultaneity
• Society yesterday not concerned initially with agreement in time