Record kept by tax officer (6)
I believe the answer is:
deputy
'officer' is the definition.
(thesaurus)
'record kept by tax' is the wordplay.
'record' becomes 'EP' (abbreviation for extended play record).
'kept by' means one lot of letters goes inside another.
'tax' becomes 'duty' (duty can mean a tax or toll).
'ep' inserted within 'duty' is 'DEPUTY'.
(Other definitions for deputy that I've seen before include "Assistant with power to act when alone" , "Stand-in, delegate" , "mine safety official" , "Appointed representative for another" , "Substitute eg for sheriff" .)