The most common and most likely answer to this crossword clue is the 10 letter word ARISTOLOGY
A
R
I
S
T
O
L
O
G
Y
Buddy explains!
The straight part
We know that "the art of dining" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the art of dining = aristology.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.