Related Clues:

• Pool ball with no number
• It's rubbed on a cue tip
• Starting signal
• 'The Hustler' prop
• 15-ball cluster
• White sale buy
• Stage prompt
• Like Dover's cliffs
• Quitter's throw-in
• Soft mineral
• Hopscotch player's buy
• Actors wait for it
• Certain writing tool
• Mnemonic device
• Low-tech hair dryer