The most common and most likely answer to this crossword clue is the 6 letter word COSHES
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More clues leading to the result COSHES
Buddy explains!
The straight part
We know that "Starts to crack open someone’s head employing sap" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case starts to crack open someone’s head employing sap = coshes.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 COSHES mean?
COSHES noun- A weapon made of leather-covered metal similar to a blackjack.
- A blunt instrument such as a bludgeon or truncheon.
- The cane.