Highbrow Charlie Girl I visit briefly (9)
I believe the answer is:
classical
'highbrow' is the definition.
(eg classical music is highbrow)
'charlie girl i visit briefly' is the wordplay.
'charlie girl' becomes 'class' (I can't justify this - if you can you should believe this answer much more).
'visit' becomes 'call' (call is a kind of visit).
'briefly' means to remove the last letter.
'call' with its final letter removed is 'cal'.
'class'+'i'+'cal'='CLASSICAL'
(Other definitions for classical that I've seen before include "Traditionally accepted" , "Genre of music" , "'highbrow'?" , "Like some music" , "Type of music as opposed to pop, jazz etc" .)