Accomplished, Dylan's first single (4)
I believe the answer is:
done
'accomplished' is the definition.
(to do something is to accomplish it)
'dylan's first single' is the wordplay.
'dylan's first' becomes 'd' (ost letter of 'dylan').
'single' becomes 'one' (a single thing - only one).
'd'+'one'='DONE'
(Other definitions for done that I've seen before include "This settled" , "(Of food) well cooked" , "Managed" , "agreed" , "Tricked" .)