Finish work on stone (4)
I believe the answer is:
Here is my best explanation:
'finish' is the definition.
('stop' can be a synonym of 'finish')
'work on stone' is the subsidiary indication.
'work' becomes 'op' (common abbreviation for 'opus').
'on' says to put letters next to each other.
'stone' becomes 'st'.
'op' put after 'st' is 'stop'.
(Other definitions for stop that I've seen before include "Cease; organ voice", "Halt, whoa, desist", "Whoa, desist", "Whoa, cease", "Prevent - desist", "as per instruction", "Knock out", "Wind up", "End or pause" and "Arrest".)