Cook's botanist in finance sources (5)
I believe the answer is:
banks
'sources' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe they are linked in a way I don't understand?
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for banks that I've seen before include "Relies" , "Financial institutions" .)