Fruit regularly featuring in Psalm One (4)

I believe the answer is:

sloe

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

I can't explain the rest of the clue.

(Other definitions for sloe that I've seen before include "Fruit often used for gin" , "Thorny bush with plum-like fruit" , "Fruit steeped in gin to make a liqueur" , "Black fruit" , "Musical study" .)

I've seen this clue in The Times.

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