In brief, a mercurial celebrity (4)

I believe the answer is:

fame

'celebrity' is the definition.
('fame' can be a synonym of 'celebrity')

'in brief a mercurial' is the wordplay.
'in' indicates a hidden word.
'FAME' is hidden in the letters of 'brief a mercurial'.

(Other definitions for fame that I've seen before include "Renown, celebrity" , "''... is the spur that the clear spirit doth raise (Lycidas, John Milton)" , "Repute" , "Prominence" , "Note" .)

I've seen this clue in The Telegraph.

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