The most common and most likely answer to this crossword clue is the 10 letter word DENOUEMENT
I've seen this crossword clue in The Daily Telegraph
D
E
N
O
U
E
M
E
N
T
More clues leading to the result DENOUEMENT
Buddy explains!

The straight part
We know that "Resolution" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case resolution = denouement.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 DENOUEMENT mean?
DENOUEMENT noun- (authorship, often used metaphorically) The conclusion or resolution of a plot.