Food for days? (5)

I believe the answer is:

salad

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'food' is the definition.
(salad is a type of food)

I cannot understand how the rest of the clue works.

(Other definitions for salad that I've seen before include "Cold dish of vegetables or fruits" , "Cold vegetable dish" , "healthy food" , "Cold dish of veg and herbs" , "Food dish" .)

I've seen this clue in the Evening Standard.

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