Having pages missing, doesn't include it (6,3)
I believe the answer is:
leaves out
'doesn't include it' is the definition.
I can't judge whether this definition defines the answer.
'having pages missing' is the wordplay.
I cannot quite understand how this works, but
'pages' could be 'leaves' (leaves can mean the pages of a book) and 'leaves' is found in the answer.
'missing' could be 'out' (I've seen this in another clue) and 'out' is located in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for leaves out that I've seen before include "evidence that spring has arrived?" , "Overlooks" , "Excludes" .)