The most common and most likely answer to this crossword clue is the 15 letter word PROFESSIONALISM
I've seen this crossword clue in Independent
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More clues leading to the result PROFESSIONALISM
- High standards for Lisa Simpson, working with energy
- Finalise proms so fantastically — evidence of a qualified person?
- Expertise to claim island is in Lake Michigan initially
- Claim I'm accepting about great boxer's expertise
- Demeanour of experts circulating mails to support admission of guilt for covering up deception
Buddy explains!
The straight part
We know that "Demeanour of experts" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case demeanour of experts = professionalism.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 PROFESSIONALISM mean?
PROFESSIONALISM noun- The status, methods, character or standards expected of a professional or of a professional organization, such as reliability, discretion, evenhandedness, and fair play.
- The use of professionals rather than amateurs in any sport etc.