Old railwaymen with points to look after (5)
I believe the answer is:
nurse
'look after' is the definition.
(I've seen this before)
'old railwaymen with points' is the wordplay.
'old railwaymen' becomes 'NUR' (National Union of Railwaymen).
'with' says to put letters next to each other.
'points' becomes 'se'.
'nur'+'se'='NURSE'
'to' is the link.
(Other definitions for nurse that I've seen before include "Nourish" , "Care for the sick" , "Hospital employee" , "Minister to" , "Tend the sick" .)