A short walk to get light railway (4)
I believe the answer is:
tram
'light railway' is the definition.
(type of transport)
'a short walk' is the wordplay.
'a short' means to remove the last letter.
'walk' becomes 'tramp' (tramp is a kind of walk).
'tramp' with its last letter removed is 'TRAM'.
'to get' acts as a link.
(Other definitions for tram that I've seen before include "Old city transport, ram on rails through streets" , "Vehicle running on rails in road" , "Former public vehicle" , "An early form of Luas in Dublin transport" , "Car on rails" .)