The most common and most likely answer to this crossword clue is the 9 letter word ADHERENCE
I've seen this crossword clue in The Guardian
A
D
H
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R
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E
More clues leading to the result ADHERENCE
- Loyalty from a duke thus, protecting queen
- Notice from this source inspiring Queen’s devotion
- Trailer, so entertaining TV show gets support
- Observant quality present in fluid dance
- Cheered with an unnatural devotion
- Being faithful, new church gets behind Christian era on Earth
- Notice new church collars ambassador about support
Buddy explains!
The straight part
We know that "Observant quality" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case observant quality = adherence.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 ADHERENCE mean?
ADHERENCE noun- A close physical union of two objects.
- Faithful support for some cause.
- An extent to which a patient continues an agreed treatment plan.