Pure, to be exact (4)

I believe the answer is:

true

I believe this is a double definition.

'pure' is the first definition.
(thesaurus)

'be exact' is the second definition.
(thesaurus)

'to' acts as a link.

(Other definitions for true that I've seen before include "Genuine, loyal" , "Factually correct" , "Genuine, real" , "Loyal; authentic" , "not showing 12 [DISHONESTY]" .)

I've seen this clue in the Evening Standard.

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