Don't eat in a quick way (4)

I believe the answer is:

fast

This clue is a double definition.

'don't eat' is the first definition.
(fasting is not eating)

'in a quick way' is the second definition.
(I know this)

(Other definitions for fast that I've seen before include "Maybe bound to spot" , "Don't scoff" , "requiring only brief exposure" , "not lento" , "fare-dodging" .)

I've seen this clue in The Daily Express.

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