The most common and most likely answer to this crossword clue is the 7 plus 8 letter word OPTICAL ILLUSION
I've seen this crossword clue in The Times
O
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More clues leading to the result OPTICAL ILLUSION
- Cause of misapprehension of coalition — one pulls out
- You won't see a lot of credibility in it
- Choice to keep iodine by sick American around California? It's deceptive
- Abandoned soul in political vision
- Over 100 Lilliputians sadly accepting love is mirage?
- What a landlady uses by implication involves one litre in a deception
- Fancy political hero harbouring American misperception!
- Shift in political soul that’s outwardly deceptive
- This is not what it appears to be
- Caution: oil spill in resort causing mirage
Buddy explains!
The straight part
We know that "Cause of misapprehension" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cause of misapprehension = optical illusion.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.