Islanders upset by nice pirates (11)

I believe the answer is:

pitcairnese

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'islanders upset by nice pirates' is the definition.
I can't tell whether this defines the answer.

'upset by nice pirates' is the wordplay.
'upset by' is an anagram indicator.
'nice'+'pirates'='nicepirates'
'nicepirates' anagrammed gives 'PITCAIRNESE'.

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