Inspiration displayed by punter at Oaks (5)
I believe the answer is:
erato
'inspiration' is the definition.
(one of the muses in Greek mythology)
'displayed by punter at oaks' is the wordplay.
'displayed by' indicates the answer is hidden within the clue.
'ERATO' can be found hidden inside 'punter at oaks'.
(Other definitions for erato that I've seen before include "Inspiring female" , "Poetic Muse ; eighteen (anag.)" , "verses she inspired" , "Arts patron" , "daughter of Zeus" .)