Drink an egg-less appetiser (3)

I believe the answer is:

sup

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

I don't understand how the remainder of the clue works.

(Other definitions for sup that I've seen before include "Drink -- eat (with the devil?)" , "Drink; take a late meal" , "Eat a late meal; sip" , "A mouthful of liquid" , "Imbibe" .)

I've seen this clue in The Hindu.

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