The most common and most likely answer to this crossword clue is the 14 letter word INSURMOUNTABLE
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result INSURMOUNTABLE
- Mare perhaps that can be covered outside? Impossible
- Cover put around album not working? It’s beyond remedy
- Impossible horse inside able to be covered!
- Remixed Neutrinos album impossible to get over
- Just can't get over that writhing US man in trouble
- Base can be given cover around so it can't be scaled
Buddy explains!
The straight part
We know that "Impossible" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case impossible = insurmountable.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 INSURMOUNTABLE mean?
INSURMOUNTABLE adjective- Incapable of being passed over, surmounted, or overcome; insuperable
- Incapable of being passed over, surmounted, or overcome; insuperable