Pig-headed beast at the wheel? (6)
I believe the answer is:
potter
'at the wheel?' is the definition.
(I've seen this before)
'pig-headed beast' is the wordplay.
'pig-headed' becomes 'p' (start (head) of the word pig).
'beast' becomes 'otter' (I have seen 'Aquatic beast' mean 'otter' so perhaps 'beast' could also mean 'otter').
'p'+'otter'='POTTER'
(Other definitions for potter that I've seen before include "Hogwarts' Harry" , "Mess (around)" , "Maker of earthenware dishes" , "Harry, Dennis or Beatrix?" , "The Harry - - books" .)