Dispatch it, wrapped in salad vegetable (8)
I believe the answer is:
celerity
'dispatch' is the definition.
(I've seen this before)
'it wrapped in salad vegetable' is the wordplay.
'wrapped in' means one lot of letters goes inside another.
'salad vegetable' becomes 'celery' (I've seen this before).
'it' placed into 'celery' is 'CELERITY'.
(Other definitions for celerity that I've seen before include "Swiftness of movement" , "Pace" , "Quickness" , "Rapidity, speediness" , "Dispatch" .)