When a vehicle gets past, this protects the head (5)
I believe the answer is:
busby
'head' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'when a vehicle gets past this protects' is the wordplay.
I cannot really see how this works, but
'vehicle' could be 'bus' (public transport vehicle) and 'bus' is present in the answer.
'past' could be 'by' (as in years gone by) and 'by' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'the' acts as a link.
Can you help me to learn more?
(Other definitions for busby that I've seen before include "Guardsman's helmet" , "Hussar's hat" , "Military fur hat" , "Guardsman's fur hat" , "Bearskin cap (colloq.)" .)