Continue to exist (6)
'continue to exist' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for endure that I've seen before include "Stomach" , "Undergo a tough time" , "Put up with - last" , "Put up with, say hardship" , "Remain in existence; suffer" .)
(Other definitions for remain that I've seen before include "Stay behind" , "Stay around" , "Airmen (anag.)" , "Stay, don't go" , "Stay (in position)" .)