Outline book of accounts unwrapped (4)
I believe the answer is:
edge
'outline' is the definition.
(thesaurus)
'book of accounts unwrapped' is the wordplay.
'book of accounts' becomes 'ledger' (I've seen this before).
'unwrapped' means to look at the middle letters (the letters which wrap the word are removed).
The centre of 'ledger' is 'EDGE'.
(Other definitions for edge that I've seen before include "Intense/striking quality" , "Guitarist with U2" , "Sharpness of mind" , "Force" , "Bite" .)