The most common and most likely answer to this crossword clue is the 3 plus 3 letter word DUM DUM
D
U
M
D
U
M
More clues leading to the result DUM DUM
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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 DUM DUM mean?
DUM DUM noun- A soft-nosed bullet that expands on impact to cause a gaping wound.