The most common and most likely answer to this crossword clue is the 8 letter word CONCLUDE
I've seen this crossword clue in The Daily Telegraph
C
O
N
C
L
U
D
E
Buddy explains!
The straight part
We know that "Wind up/judge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wind up/judge = conclude.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 CONCLUDE mean?
CONCLUDE verb- To end; to come to an end.
- To bring to an end; to close; to finish.
- To bring about as a result; to effect; to make.
- To come to a conclusion, to a final decision.
- To make a final determination or judgment concerning; to judge; to decide.
- To shut off; to restrain; to limit; to estop; to bar; generally in the passive.
- To shut up; to enclose.
- To include; to comprehend; to shut up together; to embrace.
- To deduce, to infer (develop a causal relation)