The most common and most likely answer to this crossword clue is the 11 letter word ESTABLISHED
I've seen this crossword clue in The Daily Telegraph
E
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A
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More clues leading to the result ESTABLISHED
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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 ESTABLISHED mean?
ESTABLISHED verb- To make stable or firm; to confirm.
- To form; to found; to institute; to set up in business.
- To appoint or adopt, as officers, laws, regulations, guidelines, etc.; to enact; to ordain.
- To prove and cause to be accepted as true; to establish a fact; to demonstrate.
- Having been in existence for a long time and therefore recognized and generally accepted.
- Of a religion, church etc.: formally recognized by a state as being official within that area.
- (Model, procedure, disease) Explicitly defined, described or recognized as a reference.