The most common and most likely answer to this crossword clue is the 6 letter word SAMOAN
I've seen this crossword clue in The Daily Telegraph
S
A
M
O
A
N
More clues leading to the result SAMOAN
- Polynesian blue carp that's out of depth
- Turned like beef from Pacific islands
- Islander, famous at last, with a grouse
- Polynesian bird once seen in clinic
- Islander putting a dead bird in tin
- Pacific islander with nothing sheltered in rain tree
- Islander discovering bird no longer in hospital
- Islander succeeded with a complaint
- Islander, starting to speak, has a grumble
Buddy explains!

The straight part
We know that "Islander" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case islander = samoan.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.