Related Clues:

• Kettle sound
• Snake sound
• Heckle, in a way
• Greet the villain
• '___ boy!'
• Sound of disapproval
• Ophidian sound
• Vent sound
• Greeting for the villain
• Snake's warning
• Radiator sound
• Serpent's sound
• Bad reception?
• Catcall
• Fuse sound