The most common and most likely answer to this crossword clue is the 12 letter word ACCIDENTALLY
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More clues leading to the result ACCIDENTALLY
- By chance, stress colleague grabbing passport?
- Heads of American classified counter intelligence damage friendly country without meaning to
- By chance, one new score’s interrupted by detectives
- I had bumped into Mark, someone on the same side, by chance
- Drug, helper outside ward had consumed at first by mistake
- Dealt with cynical changes by mistake
- Supporter on pitch catching papers by mistake
Buddy explains!

The straight part
We know that "by mistake" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case by mistake = accidentally.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 ACCIDENTALLY mean?
ACCIDENTALLY adverb- In an accidental manner; by chance, unexpectedly.
- Unintentionally.