Less than ten cents is not very clever (3)
I believe the answer is:
dim
'not very clever' is the definition.
I can't tell whether this defines the answer.
'less than ten cents' is the wordplay.
'less than' means to remove the last letter (not the full word).
'ten cents' becomes 'dime' (I've seen this before).
'dime' with its final letter taken away is 'DIM'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for dim that I've seen before include "Slow to learn" , "Not bright or distinct" , "Without much light" , "Lose brightness" , "Slow-witted" .)