Related Clues:

• Sibilant boo
• Cobra's "careful!"
• Steam sound
• Leaky sound
• Sound from a leaking tire
• Cobra warning
• 1960's-70's draft org.
• Sound from a tire with a hole in it
• Dismissive sound
• Evince displeasure
• Greet a villain
• Steam iron sound
• Serpentine signal
• Express displeasure
• React like a cat