Duck starts to pull out vegetable (7)
I believe the answer is:
pochard
'duck' is the definition.
(I know that pochard is a type of duck)
'starts to pull out vegetable' is the wordplay.
'starts to' suggests taking the first letters.
'vegetable' becomes 'chard' (chard is a kind of vegetable).
The initial letters of 'pull out' is 'po'.
'po'+'chard'='POCHARD'
(Other definitions for pochard that I've seen before include "Spanish wine" , "diver" , "bird" , "Type of diving duck" .)