Construction began to lay track for the new rail line.
The train is running on the rails.
curtain rail; sliding door track
Used for rails or tracks for curtains, sliding doors, drawers, etc.
I install a curtain rail.
groundwork; preparations; arrangements
Figurative use, often in the phrase レールを敷く (to lay the groundwork).
For the project's success, we need to lay the groundwork in advance.
It's not good for parents to lay out their child's future path in advance.
He deviated from life's expected track and pursued his own path.
The train was running slowly along the rails.
軌道 is a more technical term that can mean railway track or an orbit, whereas レール is the everyday word for the physical rail bars.
book; volume; script · this; present; current; in question · main; head; principal · real; genuine; regular; proper · counter for long cylindrical objects; counter for films, TV shows, etc.; counter for goals, home runs, etc.; counter for telephone calls
Loanword from English 'rail'.
curtain rail
picture rail