Vetoed fictional composition describing what might be worn at sea (9,6)

I believe the answer is:

flotation device

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'what might be worn at sea' is the definition.
I can't judge whether this definition defines the answer.

'vetoed fictional composition' is the wordplay.
'composition' is an anagram indicator (letters arranged or composed in a different order).
'vetoed'+'fictional'='vetoedfictional'
'vetoedfictional' anagrammed gives 'FLOTATION DEVICE'.

'describing' acts as a link.

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I've seen this clue in The Irish Times.

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