Accomplishing racket about nothing good (5)
I believe the answer is:
doing
'accomplishing' is the definition.
(doing is a kind of accomplishing)
'racket about nothing good' is the wordplay.
'racket' becomes 'din' (both can mean a loud noise or disturbance).
'about' indicates putting letters inside.
'nothing' becomes 'O' (looks like zero - 0).
'good' becomes 'g' (abbreviation).
'din' enclosing 'o' is 'doin'.
'doin'+'g'='DOING'
(Other definitions for doing that I've seen before include "Performing a task" , "Effecting" , "Beating (colloquial); performing" , "Carrying out action" , "Execution" .)