The most common and most likely answer to this crossword clue is the 10 letter word ADMISSIONS
I've seen this crossword clue in Financial Times
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More clues leading to the result ADMISSIONS
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The straight part
We know that "Declarations" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case declarations = admissions.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 ADMISSIONS mean?
ADMISSIONS noun- The act or practice of admitting.
- Permission to enter, or the entrance itself; admittance; entrance; access
- The granting of an argument or position not fully proved; the act of acknowledging something asserted; acknowledgement; concession.
- Acquiescence or concurrence in a statement made by another, and distinguishable from a confession in that an admission presupposes prior inquiry by another, but a confession may be made without such inquiry.
- A fact, point, or statement admitted; as, admission made out of court are received in evidence
- Declaration of the bishop that he approves of the presentee as a fit person to serve the cure of the church to which he is presented.
- The cost or fee associated with attendance or entry.