Charlie may leave after knocking back drink (6)

I believe the answer is:

cognac

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'drink' is the definition.
(Cognac is an example)

I can't explain the rest of the clue.

(Other definitions for cognac that I've seen before include "Brandy as for Napoleon (6)." , "Brandy of the French Charente" , "Liquor" , "Good brandy" , "Type of brandy" .)

I've seen this clue in The Times.

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