Crushed capers for jam (6)
I believe the answer is:
scrape
'jam' is the definition.
(thesaurus)
'crushed capers' is the wordplay.
'crushed' indicates an anagram.
'capers' is an anagram of 'SCRAPE'.
'for' acts as a link.
(Other definitions for scrape that I've seen before include "Grate; graze" , "What violinist does" , "Rake - predicament" , "Clean with edge of knife" , "Informally, an awkward situation due to rashness" .)