Debtor's burden (4)
I believe the answer is:
lien
'debtor's burden' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for lien that I've seen before include "Right to retain property until a debt is paid" , "Right to another's property, if an obligation is not discharged" , "Legal right over the Nile" , "Legal right to detain property" , "Security for a debt" .)