Utmost efforts getting over to isolated land (5)
I believe the answer is:
atoll
'isolated land' is the definition.
The definition and answer can be both natural objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'utmost efforts getting over to' is the wordplay.
'utmost efforts getting' becomes 'all' (I can't justify this - if you can you should give a lot more credence to this answer).
'over' indicates putting letters inside.
'all' going around 'to' is 'ATOLL'.
Can you help me to learn more?
(Other definitions for atoll that I've seen before include "Land around a lagoon, such as Bikini" , "Ring of coral" , "land threatened by rising sea levels" , "tropical paradise?" , "String of islands" .)