Primitive organisation associated with Cosmopolitan (15)

I believe the answer is:

unsophisticated

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'primitive organisation associated with cosmopolitan' is the definition.
I can't tell whether this definition defines the answer.

'primitive organisation associated with cosmopolitan' is the wordplay.
'primitive organisation' becomes 'un' (UN is an example. I am not sure about the 'primitive' bit.).
'associated with' says to put letters next to each other.
'cosmopolitan' becomes 'sophisticated' (similar in meaning).
'un'+'sophisticated'='UNSOPHISTICATED'

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(Other definitions for unsophisticated that I've seen before include "green" , "straightforward" , "Simple" , "Lacking experience" , "crude" .)

I've seen this clue in The Irish Times.

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