Possible Clues:

• Put the __ on: squelch
• Stopper, informally
• Put the ___ on (squelch)
• Nonsense (slang)
• Stop from happening
• Put the ___ on (stop)
• Unwelcome end, with 'the'
• 'The King and I'''s nonsense - put this on it!
• Nonsense
• Stopper, slangily