Free cinema popcorn - initially consumed for free (10)
I believe the answer is:
emancipate
'free' is the definition.
(thesaurus)
'free cinema popcorn initially consumed' is the wordplay.
'free' indicates an anagram.
'initially' indicates taking the first letters.
'consumed' becomes 'ate' (eating is a kind of consuming).
The initial letter of 'popcorn' is 'p'.
'cinema' with letters rearranged gives 'emanci'.
'emanci'+'p'+'ate'='EMANCIPATE'
'for' is the link.
(Other definitions for emancipate that I've seen before include "setting free" , "Set free" , "Free from slavery" , "Liberate" , "release" .)