The Ring used to be a Spike Jonze movie (6)
I believe the answer is:
washer
'the ring' is the definition.
(I've seen this before)
'to be a spike jonze movie' is the wordplay.
I cannot quite see how this works, but
'a' is found in the answer.
'movie' could be 'w' (W, film about George W Bush) and 'w' is found in the answer.
The remaining letters 'sher' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'used' is the link.
Can you help me to learn more?
(Other definitions for washer that I've seen before include "Flattened ring that keeps nuts secure" , "Seal to prevent leakage" , "Cleaner" , "Ring placed between two surfaces to prevent leakage, as in tap" , "Rubber ring securing joint" .)