A little nonsense removing the old deception (9)
I believe the answer is:
whitewash
'the old deception' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'a little nonsense removing' is the wordplay.
I cannot quite understand how this works, but
'a' is present in the answer.
'little' could be 'whit' (I've seen this before) and 'whit' is present in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for whitewash that I've seen before include "Deliberate cover-up of faults" , "Solution for painting walls - clean sweep of victories" , "Comprehensive defeat - type of paint" , "Cover up - wall coating" , "overwhelming defeat" .)