The most common and most likely answer to this crossword clue is the 9 letter word HESITATES
I've seen this crossword clue in The Guardian
H
E
S
I
T
A
T
E
S
More clues leading to the result HESITATES
Buddy explains!

The straight part
We know that "Stalls" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stalls = hesitates.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 HESITATES mean?
HESITATES verb- To stop or pause respecting decision or action; to be in suspense or uncertainty as to a determination.
- To stammer; to falter in speaking.
- To utter with hesitation or to intimate by a reluctant manner.