railroad track; rail line
Refers to the physical railway tracks or the rail line itself. Often used in technical or descriptive contexts.
I live near the railroad tracks, so I often hear the sound of trains.
This rail line is exclusively for freight trains.
線路 is a more general term for 'railway track' or 'line', while 鉄道線路 explicitly includes 'railroad' (鉄道), making it slightly more formal or specific.
軌道 can refer to tracks in a broader sense, including tramways or guided paths, whereas 鉄道線路 is specifically for heavy rail.
Compound of 鉄道 (railroad) and 線路 (track/line). The components are straightforward and the meaning is transparent.