Don't go on to the snow cap (4)
I believe the answer is:
stop
'don't go on' is the definition.
(I've seen this in another clue)
'the snow cap' is the wordplay.
'the snow' becomes 's' (this might be a standard abbreviation of which I'm unaware).
'cap' becomes 'top' (synonyms).
's'+'top'='STOP'
'to' is the link.
Can you help me to learn more?
(Other definitions for stop that I've seen before include "set of organ pipes" , "high card in bridge" , "Pause - prevent" , "Come to an end" , "Plug; cease" .)