The most common and most likely answer to this crossword clue is the 12 letter word FRANKENSTEIN
I've seen this crossword clue in The Guardian
F
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More clues leading to the result FRANKENSTEIN
- Tanner’s knife fashioned a work of horror
- Plain-spoken physicist ignoring one madman in laboratory
- Honest, intense work by Shelley
- Candid, in from France, over beer mug that could ruin manufacturer
- Plain scientist, not one that Shelley imagined
- Honest genius ditching one misguided one?
- Book German genius missing first international
- Loud row with physicist, one I overlooked in Gothic novel
- Plain genius, one outstanding fictional scientist
- Mistaken for a monster, outspoken scientist drops initial interest
Buddy explains!
The straight part
We know that "Mistaken for a monster" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mistaken for a monster = frankenstein.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.