The most common and most likely answer to this crossword clue is the 10 letter word CLOVERLEAF
I've seen this crossword clue in The Daily Telegraph
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Buddy explains!
The straight part
We know that "One could be lucky" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one could be lucky = cloverleaf.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 CLOVERLEAF mean?
CLOVERLEAF noun- (with plural cloverleaves) The leaf of a clover plant
- (with plural cloverleafs or cloverleaves) A cloverleaf interchange.
- To turn by following a cloverleaf, or as if by following one.
- In the form of the leaf of a clover plant; cloverleafed.