Object to one second to last on the list (7)
I believe the answer is:
itemise
'the list' is the definition.
(to itemise is to create a list)
'object to one second to last' is the wordplay.
'object' becomes 'item' (both can mean a thing).
'to one' becomes 'i' (Roman numeral).
'second' becomes 's' (common abbreviation).
'to last' becomes 'e' (I am not sure about this - if you are sure you should believe this answer much more).
'item'+'i'+'s'+'e'='ITEMISE'
'on' is the link.
Can you help me to learn more?
(Other definitions for itemise that I've seen before include "Using spell out" , "Set down separately" , "Enumerate" , "Read off list of things one by one" , "List exhaustively" .)