NODDING
- the action of a nod [n -S]
- Lower and raise one's head slightly and briefly, esp. in greeting, assent, or understanding, or to give someone a signal
- Signify or express (greeting, assent, or understanding) in this way
- Draw or direct attention to someone or something by moving one's head
- NOD, to briefly lower the head forward [v]
- Move one's head up and down repeatedly
- Have one's head fall forward when drowsy or asleep