Related Clues:

• Interrupt with a shoulder tap
• Supplement with
• Thing one can do on one's fingers
• Word heard in math class
• Attach, as a codicil
• Tack (on)
• Do the numbers
• Increase (with "to")
• Act pushy
• Contribute more
• Add free; return (ball) to play
• Include at no extra cost a restart for game
• Give away chance to get back into the game
• Interrupt, offering copper money
• Begin to speak