Prospective groom accepting new money (7)
I believe the answer is:
finance
'money' is the definition.
(finance is the management of money)
'prospective groom accepting new' is the wordplay.
'prospective groom' becomes 'fiance' (man engaged to be married).
'accepting' indicates putting letters inside (inserted letters are accepted).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'fiance' going around 'n' is 'FINANCE'.
(Other definitions for finance that I've seen before include "Money management" , "Supply funds" , "Monetary support" , "Support monetarily" , "Economics" .)