Obscure publicity material ignoring second book (4)
I believe the answer is:
blur
'obscure' is the definition.
(both can mean to vague or indistinct)
'publicity material ignoring second book' is the wordplay.
I cannot quite see how this works, but
'second' could be 'b' (B can mean second eg B-side) and 'b' is found within the answer.
The remaining letters 'lur' is a valid word which might be clued in a way I don't understand.
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 "Make less distinct" , "Smudge - Britpop band" , "Out-of-focus image" , "fade" , "Confused impression" .)