Related Clues:

• Covert sound
• Signal from a man in a trenchcoat
• Subtle ''Hey you!''
• ''Yo!''
• Low-key ''Hey!''
• Sibilant attention-getter
• '___! Pass it on ... '
• ''Take your hands off me!''
• Sibilant “Hey!”
• ''Wanna hear a secret?''
• Quiet 'Hey!'
• Hello
• Muffled ''Hey, you!''
• Discreet call
• Verbal elbow