Akademik

nod
1. verb /nɒd,nɑd/
a) To incline the head up and down, as to indicate agreement.

Even Homer nods.

b) To incline (the head) up and down, as to indicate agreement.

He nodded his head no.

Syn: shake
See Also: nod off, nod out
2. noun /nɒd,nɑd/
An instance of moving ones head as described above.

Wikipedia foundation.