Major hiding in the grass survived (8)
I believe the answer is:
remained
'survived' is the definition.
The answer and definition can be both to do with fundamental existence as well as being past participle verbs.
Maybe you can see an association between them that I don't see?
'major hiding in the grass' is the wordplay.
'major' becomes 'main' (both can mean important).
'hiding in' is an insertion indicator.
'the grass' becomes 'reed' (type of grass plant).
'main' placed into 'reed' is 'REMAINED'.
Can you help me to learn more?
(Other definitions for remained that I've seen before include "Stayed behind" , "Was left" , "Stayed put as I meander" , "didn't move" .)