The most common and most likely answer to this crossword clue is the 9 letter word COPARTNER
I've seen this crossword clue in Independent
C
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P
A
R
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More clues leading to the result COPARTNER
Buddy explains!
The straight part
We know that "associate" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case associate = copartner.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 COPARTNER mean?
COPARTNER noun- A joint partner (in a business).
- To form a joint partnership with somebody.