The most common and most likely answer to this crossword clue is the 12 letter word VERIFICATION
I've seen this crossword clue in The Times
V
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R
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F
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More clues leading to the result VERIFICATION
Buddy explains!
The straight part
We know that "Check" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case check = verification.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 VERIFICATION mean?
VERIFICATION noun- The act of verifying.
- The state of being verified.
- Confirmation; authentication.
- A formal phrase used in concluding a plea, to denote confirmation by evidence.
- The operation of testing the equation of a problem, to see whether it truly expresses the conditions of the problem.