Christian ones from a freemason, possibly (9)

I believe the answer is:

forenames

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'christian ones' is the definition.
Although both the answer and definition are plural nouns, I cannot see how they can define each other.

'a freemason possibly' is the wordplay.
'possibly' indicates an anagram.
'freemason' is an anagram of 'FORENAMES'.

'from' acts as a link.

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I've seen this clue in The Irish Independent.

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