Give in: or die! (7)
I believe the answer is:
succumb
This clue is a double definition.
'give in' is the first definition.
(synonyms)
'die' is the second definition.
(I know that succumb is a type of die)
'or' acts as a link.
(Other definitions for succumb that I've seen before include "Bow down" , "Give in, yield" , "Be fatally overwhelmed" , "Surrender" , "Give in (to disease, etc)" .)