Rudimentary amount of money? (4)
I believe the answer is:
dime
'money?' is the definition.
'rudimentary amount' is the wordplay.
'rudimentary' becomes 'dim' (I am not sure about this - if you are sure you should believe this answer much more).
'amount' becomes 'e' (e is a kind of amount).
'dim'+'e'='DIME'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for dime that I've seen before include "US ten cent coin" , "Ten cents in USA" , "US 10 cent coin" , "Ten cents piece" , "Small American coin" .)