Young attendants appearing in the book (5)
I believe the answer is:
pages
'young attendants' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for pages that I've seen before include "boys in the hotel" , "Sheets of a book" , "See 16" , "Young attendants" , "Book leaves" .)