The most common and most likely answer to this crossword clue is the 9 letter word DETAINING
I've seen this crossword clue in Financial Times
D
E
T
A
I
N
I
N
G
Buddy explains!
The straight part
We know that "Stopping" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stopping = detaining.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 DETAINING mean?
DETAINING verb- To keep someone from proceeding by holding them back or making claims on their attention.
- To put under custody.
- To keep back or from; to withhold.
- To seize goods for official purposes.
- The act by which someone is detained; detention.