Related Clues:

• Clandestine call
• Near-silent 'Hey!'
• 'Hey … you!'
• Hey, the quiet way
• Start of a whispered comment
• "Hey!" in class
• Cry for attention?
• Sibilant attention getter
• Low-key 'Hey!'
• ''Hey, you . . .''
• ''Hey, Buddy!''
• Discreet summons
• Attention-getting whisper
• Sound for attention
• "Yo!" in the library