Vegetable from greengrocers we'd established (5)
I believe the answer is:
swede
'vegetable' is the definition.
(I know that swede is a type of vegetable)
'from greengrocers we'd established' is the wordplay.
'from' says the answer is hidden in the clue.
'SWEDE' can be found hidden inside 'greengrocers wed established'.
(Other definitions for swede that I've seen before include "plant" , "Sort of turnip - one from Scandinavia?" , "Northern European" , "Root vegetable - European" , "N European" .)