Married with ring - outstanding (4)
I believe the answer is:
owed
'outstanding' is the definition.
('owed' can be a synonym of 'outstanding')
'married with ring' is the wordplay.
'married' becomes 'wed' ('wed' can be similar in meaning to 'married').
'with' is a charade indicator (letters next to each other).
'ring' becomes 'o'.
'wed' after 'o' is 'OWED'.
(Other definitions for owed that I've seen before include "to be paid" , "Outstanding" , "Had a duty to pay" , "Was indebted" , "Had an obligation to pay" .)