The most common and most likely answer to this crossword clue is the 12 letter word FORE-AND-AFT
I've seen this crossword clue in Financial Times
F
O
R
E
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A
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D
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A
F
T
More clues leading to the result FORE-AND-AFT
Buddy explains!

The straight part
We know that "from bow to stern" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case from bow to stern = fore-and-aft.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 FORE-AND-AFT mean?
FORE-AND-AFT adjective- (of the orientation of the sails of a ship) parallel with the keel, that is, going from bow to stern (as opposed to square-rigged).