Single advance of funds, we hear (4)
I believe the answer is:
lone
'single' is the definition.
(synonyms)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for lone that I've seen before include "Solitary, sounds like advance" , "Single and isolated" , "Companionless" , "Solitary, without companions" , "The ... Ranger, fictional masked cowboy" .)