Old mortgage deal, in part (4)

I believe the answer is:

aged

'old' is the definition.
('aged' can be similar in meaning to 'old')

'mortgage deal in part' is the wordplay.
'in part' indicates a hidden word.
'AGED' is hidden in the letters of 'mortgage deal'.

(Other definitions for aged that I've seen before include "not like a callow youth" , "Old or ancient" , "way over the hill" , "Got older" , "Antiquated" .)

I've seen this clue in The Times.

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