Sun-worshipper in this atoll (6)
I believe the answer is:
bikini
'this atoll' is the definition.
(I've seen this before)
'sun-worshipper in' is the wordplay.
I cannot really understand how this works, but
'in' is found in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bikini that I've seen before include "Skimpy beachwear" , "Kind of swimsuit" , "Skimpy two-piece swim wear" , "two-piece outfit" , "Minuscule bathing costume for woman" .)