Not strong drink? (4)

I believe the answer is:

mild

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'not strong' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for mild that I've seen before include "Moderate, temperate" , "Calm" , "Far from extreme" , "Moderately warm - type of beer" , "Gentle in temper and disposition" .)

I've seen this clue in the Evening Standard.

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