The most common and most likely answer to this crossword clue is the 8 letter word CLOTHIER
C
L
O
T
H
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E
R
More clues leading to the result CLOTHIER
- Tailor is fool to hurry back of blazer
- Idiot greeting King Edward’s tailor
- Idiot yesterday in Paris, one with lots of duds
- Tailor item in sale acquired by nouveau riche
- Woman’s following fool about Independent’s arbiter of fashion?
- Shopkeeper disinclined to get in ground rice
- Fool the woman employing one who makes dresses?
- Fool, one taken in by her dressmaker?
- Fool greeting monarch — man among the duds?
- Fool that woman looking over one tailor
Buddy explains!

The straight part
We know that "arbiter of fashion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case arbiter of fashion = clothier.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 CLOTHIER mean?
CLOTHIER noun- A person who makes or sells cloth or clothing.