Possible Clues:

• Wildly greet us, giving a wave, perhaps
• Eg, shrug or wave
• The bird, for one
• Handy expression for joke you're listening to
• Gets knocked out, on river - by wave, perhaps?
• Expressive physical movement
• Perhaps greet us with a wave
• Expressive motion
• Action done for show
• Managing to greet us with a sign