Honest expression of agreement (4)

I believe the answer is:

true

This clue is a double definition.

'honest' is the first definition.
(I know that honest can be written as true)

'expression of agreement' is the second definition.
(I've seen this before)

(Other definitions for true that I've seen before include "Loyal; authentic" , "Veritable" , "Veracious" , "Accurate, exact" , "Genuine; faithful" .)

I've seen this clue in The Globe and Mail.

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