The most common and most likely answer to this crossword clue is the 8 letter word LUMINARY
I've seen this crossword clue in The Daily Telegraph
L
U
M
I
N
A
R
Y
More clues leading to the result LUMINARY
- Not initially miserable, one not locally a celebrity
- Guiding light for alumni working on railway
- Worthy arrangement of family run without force
- Star of the road in 354 days, briefly
- Soho celebrity here is playing harmoniously
- Lay in rum, rum for famous person
- Learner, university girl, entertaining trendy celebrity
- In a line behind smoker… great!
- An authority on the intricate mural in Yukon's capital
- Guiding light from tower in regularly cloudy environment
Buddy explains!

The straight part
We know that "celebrity" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case celebrity = luminary.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 LUMINARY mean?
LUMINARY noun- One who is an inspiration to others; one who has achieved success in their chosen field; a leading light.
- A body that gives light; especially, one of the heavenly bodies.
- An artificial light; an illumination.