Related Clues:

• Champagne overflow
• Pillow filling, sometimes
• Latte topping
• Head in the saloon
• White water feature
• Mattress type
• Shaving facilitator
• Insubstantial stuff
• Shipping cushion
• Head of 42-Across
• Shaver's purchase, perhaps
• Ale head
• Head for a bar?
• Head in the bar
• Form bubbles