Close friend's secret (8)

I believe the answer is:

intimate

I believe this clue is a double definition.

'close friend's' is the first definition.
(thesaurus)

'secret' is the second definition.
(thesaurus)

(Other definitions for intimate that I've seen before include "Suggest to trusted friend?" , "Thick" , "Hint to a familiar friend" , "pal" , "Familiar; imply" .)

I've seen this clue in The Telegraph.

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