Discontinue stay (4)
I believe the answer is:
stop
This clue is a double definition.
'discontinue' is the first definition.
('stop' can be a synonym of 'discontinue')
'stay' is the second definition.
('stop' can be a synonym of 'stay')
(Other definitions for stop that I've seen before include "colon, say" , "Plug; cease" , "Knock out" , "break" , "port of call" .)