The most common and most likely answer to this crossword clue is the 8 letter word CHASSEUR
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The straight part
We know that "attendant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case attendant = chasseur.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 CHASSEUR mean?
CHASSEUR noun- A soldier equipped for rapid movement; also, any of several light infantry regiments, especially in France.
- A servant or attendant.
- A hotel messenger, especially in France.
- A hunter or huntsman.
- A dish of meat cooked in a sauce containing mushrooms, shallots and white wine.