The most common and most likely answer to this crossword clue is the 6 plus 2 plus 6 letter word BARREL OF LAUGHS
I've seen this crossword clue in The Times
B
A
R
R
E
L
O
F
L
A
U
G
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S
More clues leading to the result BARREL OF LAUGHS
Buddy explains!
The straight part
We know that "The butt of jokes" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the butt of jokes = barrel of laughs.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.