Fluids doctored as beverages (4)

I believe the answer is:

inks

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'fluids' is the definition.
(ink is a kind of fluid)

I don't understand the remainder of the clue.

(Other definitions for inks that I've seen before include "Printers' media" , "Printing fluids" , "Sink beneath writing fluids" , "Liquids used for printing" , "Printers' mediums" .)

I've seen this clue in the Evening Standard.

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