Related Clues:

• Call to attention?
• Subdued attention-getter
• ... a cheater in class
• Discreet attention-getter
• Sound that may turn heads
• Subtler alternative to ''Yo!''
• It may precede the sharing of a secret
• Subtle "Yo!"
• "Hey!"
• 'What's shakin'?'
• ''Hey, pal, over here!''
• Informal conversation starter
• "Ahem!"
• Furtive call
• "Over here!" noise