Dont go and support (4)
I believe the answer is:
stay
'support' is the definition.
(stay is a kind of support)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for stay that I've seen before include "Period in one place" , "Board; continue" , "Remain; prop" , "Put off - visit" , "Stick around" .)