Survive, determined to correct terrible evil (7)
I believe the answer is:
outlive
'survive' is the definition.
(I know that survive can be written as outlive)
'determined to correct terrible evil' is the wordplay.
I cannot really see how this works, but
'determined' could be 'out' and 'out' is located in the answer.
an anagram of 'evil' is 'live' which is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for outlive that I've seen before include "Go on longer than" , "weather" , "Die after" , "Survive beyond (another)" , "Survive longer than" .)