Bookworm hesitates back and forth over poster (6)
I believe the answer is:
reader
'bookworm' is the definition.
(I've seen this in another clue)
'hesitates back and forth over poster' is the wordplay.
I cannot quite understand how this works, but
'over' could be 're' and 're' is found within the answer.
'poster' could be 'ad' (short for advert) and 'ad' is located in the answer.
The remaining letters 'er' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for reader that I've seen before include "Peruser of texts" , "University lecturer - text book" , "Publisher's selector" , "Times subscriber, perhaps?" , "Peruser of text" .)