Flee island out of altruism (4-6)

I believe the answer is:

self-denial

'altruism' is the definition.
(thesaurus)

'flee island out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'flee'+'island'='fleeisland'
'fleeisland' is an anagram of 'SELF-DENIAL'.

'of' is the link.

(Another definition for self-denial that I've seen is " Unwillingness to gratify one's own desires".)

I've seen this clue in The Daily Express.

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