Genteel umpire - popular journalist (7)
I believe the answer is:
refined
'genteel' is the definition.
(similar in meaning)
'umpire popular journalist' is the wordplay.
'umpire' becomes 'ref' (short for referee).
'popular' becomes 'in' ('in' can mean trendy).
'journalist' becomes 'ed' (short for editor).
'ref'+'in'+'ed'='REFINED'
(Other definitions for refined that I've seen before include "Free from vulgarity" , "Just like the cultured" , "Polished" , "Tasteful; genteel" , "Elegant, cultured" .)