The most common and most likely answer to this crossword clue is the 12 letter word SPELLCHECKER
I've seen this crossword clue in Financial Times
S
P
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L
L
C
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C
K
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R
More clues leading to the result SPELLCHECKER
Buddy explains!
The straight part
We know that "Might one be confused by form from/Dumbledore, for example" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case might one be confused by form from/dumbledore, for example = spellchecker.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 SPELLCHECKER mean?
SPELLCHECKER noun- A software application that attempts to verify spelling in a document.