The most common and most likely answer to this crossword clue is the 8 letter word OBSCURER
I've seen this crossword clue in The Times
O
B
S
C
U
R
E
R
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 OBSCURER mean?
OBSCURER adjective- Dark, faint or indistinct.
- Hidden, out of sight or inconspicuous.
- Difficult to understand.
- Not well-known.
- Unknown or uncertain; unclear.
- One who, or that which, obscures.