Advance unaccompanied, so to speak (4)
I believe the answer is:
loan
'advance' is the definition.
(an advance is a loan)
'unaccompanied so to speak' is the wordplay.
'unaccompanied' becomes 'lone' (on one's own).
'so to speak' shows a homophone (sound like).
'lone' is a homophone of 'LOAN'.
(Other definitions for loan that I've seen before include "Money borrowed at interest" , "Cash advance" , "Overdraft" , "It's given temporarily" , "One acquired temporarily" .)