Related Clues:

• Less threatening sound than 'grr'
• Sound at the pound
• Corgi comment
• Sound from a woofer?
• Dog's sound
• Lab greeting
• 'Ruff!'
• Woofer's output?
• Hidden theme of the puzzle
• Response to "Speak!"
• Sandy snippet
• Sound from a kennel
• Remark from Rex
• Sound from a woofer
• It might mean "I'm hungry!"