The most common and most likely answer to this crossword clue is the 8 letter word VETERANS
I've seen this crossword clue in Financial Times
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More clues leading to the result VETERANS
Buddy explains!
The straight part
We know that "People with long experience" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case people with long experience = veterans.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 VETERANS mean?
VETERANS noun- A person with long experience of a particular activity.
- A group, animal, etc. with long experience of a particular activity.
- A person who has served in the armed forces, especially an old soldier who has seen long service; also called a war veteran to distinguish from veterans that weren't in armed conflict.