Piece of work from artist, a sketch (4)
I believe the answer is:
task
'piece of work' is the definition.
(thesaurus)
'from artist a sketch' is the wordplay.
'from' indicates the answer is hidden within the clue.
'TASK' is hidden in the letters of 'artist a sketch'.
(Other definitions for task that I've seen before include "Job, undertaking" , "exercise" , "Difficult piece of work" , "Errand, duty" , "Assignment" .)