Highlander, perhaps heading away from the racecourse (4)
I believe the answer is:
scot
'highlander' is the definition.
(I've seen this in another clue)
'heading away from the racecourse' is the wordplay.
'heading away from' means to remove the first letter.
'the racecourse' becomes 'ascot' (British racecourse).
'ascot' with its initial letter taken away is 'SCOT'.
'perhaps' acts as a link.
(Other definitions for scot that I've seen before include "Payment" , "Stevenson was one" , "one from the North of Britain" , "someone with devolved parliament?" , "Ancient tax" .)