Fellow turning to move his head? (3)
I believe the answer is:
nod
'move his head?' is the definition.
'nod' can be an answer for 'move' (nodding is a kind of moving). I'm unsure of the 'his head?' bit.
'fellow turning' is the wordplay.
'fellow' becomes 'don' (both can mean an academic).
'turning' is a reversal indicator.
'don' backwards is 'NOD'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for nod that I've seen before include "Agree non-verbally" , "Asleep in the land" , "'A . . . is as good as a wink to a blind horse'" , "positive sign" , "Show assent" .)