Consecutive atoms show fruit (6)

I believe the answer is:

tomato

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

I cannot understand how the rest of the clue works.

(Other definitions for tomato that I've seen before include "A motto, strangely, for this fruit" , "Fruit-vegetable" , ""Plum" or "beef" fruit?" , "Salad fruit or berry" , "In France, it's a love apple" .)

I've seen this clue in The Guardian.

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