The most common and most likely answer to this crossword clue is the 8 letter word PUNCH-UP
I've seen this crossword clue in The Times
P
U
N
C
H
-
U
P
Buddy explains!
The straight part
We know that "fight" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fight = punch-up.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 PUNCH-UP mean?
PUNCH-UP noun- A fight with the fists.
- To attack or target a group of greater power and/or status than oneself.