Transport of vehicle by railway ... (5)
I believe the answer is:
carry
'transport' is the definition.
(I know that transport can be written as carry)
'vehicle by railway' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'by' means one lot of letters go next to another.
'railway' becomes 'ry' (abbreviation for railway).
'car'+'ry'='CARRY'
'of' is the link.
(Other definitions for carry that I've seen before include "Convey, tote" , "Bear, tote" , "Transport, fetch" , "Stock" , "Transport; transmit" .)