Record sections for railway lines (6)
I believe the answer is:
tracks
'lines' is the definition.
(track is a kind of line)
'record sections for railway' is the wordplay.
I cannot quite see how this works, but
'railway' could be 'rack' (rack railway is a kind of railway) and 'rack' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for tracks that I've seen before include "Marks left in ground by animals" , "Spoo" , "Follows the marks of an animal" , "Trails" , "Rough paths; traces" .)