Not lying, being honest (7)

I believe the answer is:

upright

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'honest' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for upright that I've seen before include "deserving respect" , "Vertical like rugby goal post" , "extremely reliable?" , "Honest; goal-post" , "beyond reproach" .)

I've seen this clue in the Evening Standard.

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