Herb that makes money (4)
I believe the answer is:
mint
'herb' is the definition.
(mint is a kind of herb)
'money' is the wordplay.
I cannot really understand how this works, but
'money' could be 'm' (abbreviation used in economics) and 'm' is found within the answer.
The remaining letters 'int' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'that makes' acts as a link.
Can you help me to learn more?
(Other definitions for mint that I've seen before include "and 18 Down: Southern US cocktail" , "Aromatic herb - perfect" , "Forge" , "but not used" , "Large sum of money" .)