The most common and most likely answer to this crossword clue is the 8 letter word APPENDIX
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More clues leading to the result APPENDIX
- A very soft goal upset team, in addition
- Part of book that may come out in the theatre
- A photographer's first photographs appearing around last supplement
- Arranged index on a couple of pages: it may be at back of book
- A very quiet finish before nine’s coda
- A two-page conclusion with one Times supplement?
- Reading matter a writer put on page ten in Le Monde
- Something that may be added or removed?
- Article with two pages to conclude one Times supplement
- Bit at end of book that might be taken out?
Buddy explains!

The straight part
We know that "Part of book that may come out in the theatre" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of book that may come out in the theatre = appendix.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does APPENDIX mean?
APPENDIX noun- Something attached to something else; an attachment or accompaniment.
- A text added to the end of a book or an article, containing additional information.
- The vermiform appendix, an inner organ that can become inflamed.
- Any process, prolongation or projection.