Train fellows who ran about a mile, maybe (7)
I believe the answer is:
railmen
'train fellows' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'ran about a mile maybe' is the wordplay.
'about' is an insertion indicator.
'maybe' is an anagram indicator.
'mile' is an anagram of 'ilme'.
'ran' placed around 'ilme' is 'RAILMEN'.
'who' acts as a link.
Can you help me to learn more?
(Other definitions for railmen that I've seen before include "Train under their supervision" , "They've made tracks" , "On-line workers" .)