Light lunch (5)
I believe the answer is:
salad
'light lunch' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for salad that I've seen before include "One may well be green" , "A dish of lettuce and vegetables" , "Lettuce, cucumber etc" , "vegetarian dish" , "Cold dish of vegetables or fruits" .)