Film actor taking top off (5)
I believe the answer is:
layer
'film' is the definition.
(film can mean a thin layer of something)
'actor taking top off' is the wordplay.
'actor' becomes 'player' (synonyms).
'taking top off' means to remove the first letter.
'player' with its initial letter removed is 'LAYER'.
(Other definitions for layer that I've seen before include "Stratum, tier" , "plate?" , "One producing eggs" , "Bed - hen" , "Thickness of material or earth - relay it" .)