Office worker a problem for librarian (10)
I believe the answer is:
bookkeeper
'for librarian' is the definition.
(thesaurus)
'office worker a problem' is the wordplay.
I cannot quite understand how this works, but
'a' could be 'per' (eg 'one a day' means 'one per day') and 'per' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for bookkeeper that I've seen before include "who works to maintain balance" , "Business occupation" , "Accounts official" , "accountant" , "person responsible for financial oversight" .)