Bread from trolley (4)
I believe the answer is:
roll
'bread' is the definition.
(roll is a kind of bread)
'from trolley' is the wordplay.
'from' indicates a hidden word.
'ROLL' can be found hidden inside 'trolley'.
(Other definitions for roll that I've seen before include "Bun" , "Small round piece of bread" , "Bakery product" , "Register - for continental breakfast?" , "Bread - list - drumbeats" .)