Film holder (4)
I believe the answer is:
reel
'film holder' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reel that I've seen before include "Part of a film; stagger" , "Show astonishment" , "Film spool" , "Lively dance and angler's spool" , "Fishing rod attachment" .)