Pawnbroker with a ring, initially doubtful (7)
I believe the answer is:
unclear
'doubtful' is the definition.
(I've seen this before)
'pawnbroker with a ring initially' is the wordplay.
'pawnbroker' becomes 'uncle' (old-fashioned term for a pawnbroker).
'with' says to put letters next to each other.
'initially' says to take the initial letters.
The first letter of 'ring' is 'r'.
'uncle'+'a'+'r'='UNCLEAR'
(Other definitions for unclear that I've seen before include "Cloudy or opaque" , "Not obvious, obscure" , "An ulcer (anag)" , "Ill-defined or not easily understood" , "Doubtful" .)