Related Clues:

• Subtle auction bid indicator
• Make a slip
• Bedtime "Land"
• OK sign, maybe
• Indicate uh-huh
• Signal at Christie's
• Start to nod off
• Nonverbal 'yes'
• "Go ahead" signal
• Nonverbal assent
• Indication of a green light
• Acknowledge silently
• Use your head positively?
• Wordless OK
• Wynken and Blynken's companion