The most common and most likely answer to this crossword clue is the 8 letter word OUT-TAKE
I've seen this crossword clue in The Guardian
O
U
T
-
T
A
K
E
Buddy explains!
The straight part
We know that "which didn’t make the final edit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case which didn’t make the final edit = out-take.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.