The most common and most likely answer to this crossword clue is the 4 plus 2 letter word HEAD ON
I've seen this crossword clue in The Daily Telegraph
H
E
A
D
O
N
More clues leading to the result HEAD ON
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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 HEAD ON mean?
HEAD ON noun- A collision from the front.
- Direct, abrupt, blunt or unequivocal; not prevaricating.
- Of a collision, from the front or in the direction of motion.