Last of atheist philosopher’s articles for union (9)

I believe the answer is:

trousseau

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'last of atheist philosopher's articles for union' is the definition.
I can't tell whether this defines the answer.

'last of atheist philosopher's' is the wordplay.
'last of' indicates one should take the final letters.
'philosopher' becomes 'rousseau' (Rousseau is an example).
The last letter of 'atheist' is 't'.
't'+'rousseau'='TROUSSEAU'

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(Other definitions for trousseau that I've seen before include "not top-drawer stuff" , "train etc" , "Bride's clothes, linen, etc" , "Union's present" , "Clothes collected for a purpose" .)

I've seen this clue in The Times.

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