The most common and most likely answer to this crossword clue is the 8 letter word STRANGLE
I've seen this crossword clue in Financial Times
S
T
R
A
N
G
L
E
More clues leading to the result STRANGLE
- Suppress line in novel
- Society figure not one to suppress
- Throttle holy man with right point of view
- Smother last bit of strudel in rum
- Just ran gleefully, holding throttle
- Kill foreigner with the other hand finally pushed slightly forward
- Suppress novel about Labour leader
- Suppress prominent figure not offering a view
- Deviant wears leather-tipped gag
- Learner restricted by unusual throttle
Buddy explains!

The straight part
We know that "Kill" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case kill = strangle.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 STRANGLE mean?
STRANGLE noun- A trading strategy using options, constructed through taking equal positions in a put and a call with different strike prices, such that there is a payoff if the underlying asset's value moves beyond the range of the two strike prices.
- To kill someone by squeezing the throat so as to cut off the oxygen supply; to choke, suffocate or throttle.
- To stifle or suppress.
- To be killed by strangulation, or become strangled.
- To be stifled, choked, or suffocated in any manner.