The most common and most likely answer to this crossword clue is the 8 letter word ASSASSIN
A
S
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More clues leading to the result ASSASSIN
- A sauce eaten by wrong butcher?
- Killer who has a cheek, interrupting crime
- Booth, for example, with Charlie and Jenny in?
- He ices a couple of out-of-date cakes on the spot
- A second error by crack troops exposing murderer
- Pair of idiots at home – one’s a killer!
- One who kills a couple of idiots at home
- One making hits popular by the Blockheads
- Two imbeciles at home revealing killer
- Killer donkeys at home
Buddy explains!

The straight part
We know that "Killer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case killer = assassin.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 ASSASSIN mean?
ASSASSIN noun- A member of the Nizari Ismaili Muslim community of the Alamut Period
- Someone who intentionally kills a person, especially a professional who kills a public or political figure.
- Any ruthless killer.
- To assassinate.