Don't show skin (4)
I believe the answer is:
hide
I believe this is a double definition.
'don't show' is the first definition.
(hiding is the opposite of showing)
'skin' is the second definition.
(I know that skin can be written as hide)
(Other definitions for hide that I've seen before include "Take cover - skin" , "Bury" , "Keep quiet" , "Screen; skin" , "Secrete, conceal" .)