L branch cable railway chevron cog railway crankiness crookedness dogleg el electric railway elevated elevated railway embankment feeder feeder line flexuosity gravity-operated railway hairpin horse railway junction light railroad line main line metro monorail rack railway rack-and-pinion railway rail rail line railroad railway roadbed roadway sidetrack siding street railway streetcar line subway terminal terminus track tram tramline trestle trolley line trunk trunk line tube turnout underground zag zig zigzag zigzaggery