Dandy loudly goes to work (3)
I believe the answer is:
fop
'dandy' is the definition.
(I know that dandy can be written as fop)
'loudly goes to work' is the wordplay.
'loudly' becomes 'f' (short for forte - 'loud' in music).
'goes to' says to put letters next to each other.
'work' becomes 'op' (short for opus).
'f'+'op'='FOP'
(Other definitions for fop that I've seen before include "fashionable type" , "One affected" , "A dandy, overdressed man" , "he enjoys the finest dressing" , "Man excessively concerned with fashion" .)