Everyone comes round to reef (5)
I believe the answer is:
atoll
'reef' is the definition.
(atoll is a kind of reef)
'everyone comes round to' is the wordplay.
'everyone' becomes 'all' (all people).
'comes round' means one lot of letters goes inside another.
'all' going around 'to' is 'ATOLL'.
(Other definitions for atoll that I've seen before include "Coral isle" , "Key" , "Bikini, perhaps" , "Coral island surrounding a lagoon" , "Circular coral reef" .)