The most common and most likely answer to this crossword clue is the 9 letter word CONSTRUES
I've seen this crossword clue in The Times
C
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More clues leading to the result CONSTRUES
Buddy explains!

The straight part
We know that "explains" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case explains = construes.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 CONSTRUES mean?
CONSTRUES verb- To interpret or explain the meaning of something.
- (grammar) To analyze the grammatical structure of a clause or sentence; to parse.
- (grammar) To admit of grammatical analysis.
- To translate.
- To infer.