Fonda's role in "My Darling Clementine” (4)
I believe the answer is:
earp
'fonda's role in my darling clementine' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for earp that I've seen before include "Wyatt --, US law officer" , "Wyatt - - (US marshal)" , "Wyatt --, Tombstone lawman" , "Wyatt - (O.K. Corral)" , "Wyatt -, renowned US lawman" .)