Salad fruit (6)
I believe the answer is:
tomato
'salad fruit' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for tomato that I've seen before include "Red fruit eaten as veg" , "Part of a BLT sandwich" , "Salad fruit or berry" , "Fruit-vegetable" , "that's suitable to eat" .)