Preserve; rescue (4)
I believe the answer is:
save
This clue is a double definition.
'preserve' is the first definition.
(synonyms)
'rescue' is the second definition.
(saving is a kind of rescuing)
(Other definitions for save that I've seen before include "Rescue; store" , "Set aside" , "Rescue for a rainy day?" , "Keep" , "Salvage" .)