Related Clues:

• Furtive attention-getter
• Alternative to 'Hey!'
• Soft "Over here!"
• Cheater's sound during a test
• Hushed "Hey!"
• ''Hey!''
• It ain't quite "Hey!"
• ''Hey!'' in a library
• Covert sound
• Signal from a man in a trenchcoat
• Subtle ''Hey you!''
• Low-key ''Hey!''
• Sibilant attention-getter
• Inmate's dream
• '___! Pass it on ... '