The most common and most likely answer to this crossword clue is the 9 letter word TERMINATE
I've seen this crossword clue in Financial Times
T
E
R
M
I
N
A
T
E
More clues leading to the result TERMINATE
- End the heartless destruction of minaret
- Call in at start of exercise – or finish
- Stop bullying entire team drained of energy
- Stop unpleasant characters barring entrance in gallery
- Finish second half of season in team that’s hammered
- Spell with natural sounding finish
- Stop for a short time after queen enters gallery
- To finish, call in on mischief maker
- Stop meter in taxi only half way out
- Kill insect eating gnat after wings torn off
Buddy explains!

The straight part
We know that "Stop" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stop = terminate.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 TERMINATE mean?
TERMINATE verb- To end, especially in an incomplete state.
- To set or be a limit or boundary to.
- To kill.
- To end the employment contract of an employee; to fire, lay off.
- Of a mode of transport, to end its journey; or of a railway line, to reach its terminus.
- Terminated; limited; bounded; ended.
- Having a definite and clear limit or boundary; having a determinate size, shape or magnitude.
- Expressible in a finite number of terms; (of a decimal) not recurring or infinite.