The most common and most likely answer to this crossword clue is the 6 letter word BEHEAD
I've seen this crossword clue in The Times
B
E
H
E
A
D
More clues leading to the result BEHEAD
- What killer might do to act as leader
- Execute that man bathed in a little sweat?
- One way to punish live leader?
- Have leading role to execute
- Assume leading role at school: wield the axe!
- Top diplomat wears decoration
- Top husband in contest getting promotion
- Take top off using blade handle around edges
- Remove a vital part of Shed’s insides during ball
- Ambassador in sight of guillotine
Buddy explains!

The straight part
We know that "execute" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case execute = behead.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 BEHEAD mean?
BEHEAD verb- To remove the head of; to cut someone's head off.