Truck coming from Ayr rolled over (5)
I believe the answer is:
lorry
'truck' is the definition.
(lorry is a kind of truck)
'coming from ayr rolled over' is the wordplay.
'coming from' indicates a hidden word.
'over' shows that the letters should be reversed in order.
'yrrol' is hidden within 'ayr rolled'.
'yrrol' written backwards gives 'LORRY'.
(Other definitions for lorry that I've seen before include "Commercial vehicle" , "HGV" , "Large truck" , "Industrial vehicle" , "Large motor vehicle for transporting goods" .)