Related Clues:

• Endorsement
• Silent assent
• Positive response
• ''You there''
• 'Uh-huh' equivalent
• Ear-grabbing sound
• Affirmation
• ''Want to hear a secret?''
• Cry for attention
• Agree, in a way
• Doze off
• Silent O.K.
• Silent approval
• Auction bid
• Gesture of acknowledgement