Related Clues:

• It can give you an edge
• Bad mood
• Sharpen, in a way
• Tonsorial tool
• Car seat attachment
• Barber's device
• Work on the cutting edge
• Seat belt, e.g.
• Old punisher
• See 6 Across
• Barber-chair dangler
• Barbershop accessory
• Rein, e.g.
• Sharpen a razor
• Helmet attachment, perhaps