The most common and most likely answer to this crossword clue is the 8 letter word ADDENDUM
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More clues leading to the result ADDENDUM
- Extra study adopted by a theologian, with some hesitance
- Publicity over animal sanctuary scandal upset rider
- . Extra item a divine conclusion? I’m not sure
- Damn! Dude has burst appendix
- Extra named Dud cast
- An emu three daughters trained for rider
- PS: Tipsy dad and mummy regularly hugging, close
- A few more pages thrown in to madden Dumbledore
- Edmund died with a burst appendix
- A literary supplement?
Buddy explains!

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 ADDENDUM mean?
ADDENDUM noun- Something to be added; especially text added as an appendix or supplement to a document.
- A postscript.
- The height by which the tooth of a gear projects beyond (outside for external, or inside for internal) the standard pitch circle or pitch line.