The most common and most likely answer to this crossword clue is the 6 letter word BARNEY
I've seen this crossword clue in Financial Times
B
A
R
N
E
Y
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 BARNEY mean?
BARNEY noun- A lark, a romp, some fun.
- A hoax, a humbug, something that is not genuine, a rigged or unfair sporting contest.
- (Harvard University slang) A poor recitation.
- A noisy argument.
- A minor physical fight.
- (Boston) A student at Harvard University.
- (Harvard University slang) To recite badly; to fail.
- To argue, to quarrel.
- Insane crazy, loony.
- (pejorative slang) A police officer, usually one perceived as inferior or overzealous.