Related Clues:

• Whispered sound
• Street peddler's opener?
• Attention getter
• Warning
• Attention-getting sound
• ''Hey, bud!''
• Cousin of 'ahem'
• ''Hey, Mac!''
• Call for attention
• Head-turner
• Sibilant exclamation
• Call to share a secret?
• Verbal nudge
• Attention-getter, in the audience
• ''Hey, you!''