Obscure book recommendation — book withdrawn (4)
I believe the answer is:
blur
'obscure' is the definition.
(both can mean to vague or indistinct)
'book recommendation book withdrawn' is the wordplay.
I cannot quite understand how this works, but
'book' could be 'b' (abbreviation for book) and 'b' is found in the answer.
The remaining letters 'lur' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for blur that I've seen before include "Smudge - Britpop band" , "Obscure; smudge" , "Obfuscate" , "Indistinct representation - obscure" , "Make vague" .)