Island battered in conclusion, briefly (6)
I believe the answer is:
tahiti
'island' is the definition.
(Tahiti is an example)
'battered in conclusion briefly' is the wordplay.
'battered' becomes 'hit'.
'in' means one lot of letters goes inside another.
'conclusion' becomes 'tail'.
'briefly' means to remove the last letter.
'tail' with its last letter removed is 'tai'.
'hit' inserted within 'tai' is 'TAHITI'.
(Other definitions for tahiti that I've seen before include "I hit at this exotic island" , "South Pacific island, capital Papeete" , "South Seas island, capital Papeete" , "An isle in the South Seas" , "Society member" .)