Looks positive albeit half negative! (4)
I believe the answer is:
'looks' is the definition.
The answer and definition can be both acts as well as being plural nouns.
Perhaps they are linked in a way I don't understand?
'positive albeit half negative' is the wordplay.
I cannot quite understand how this works, but
'negative' could be 'no' (no is a kind of negative) and 'no' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for nods that I've seen before include "Indicates assent" , "Signals assent" , "is about to crash?" , "Shows assent" , "Non-verbal indications of assent" .)