Related Clues:

• It can be chalked up
• White ball on slate
• Slamming door, perhaps
• Signal to start dancing that's needed during break
• It's often behind the eight ball
• It's used in snooker and on stage
• A wink or a nod, maybe
• Hint coming from line, we hear
• Stick with a blue tip, maybe
• Signal to go on, say
• Entrance signal
• Banking instrument?
• Prompt's prompt
• Implement used for breaking
• Being prompt, this might be tipped