carriage
n. countablen. one of the separate sections of a train that carries passengers. In older times, it also meant a vehicle with four wheels pulled by horses.
n. a separate section of a train designed for passenger transport; also, a four-wheeled horse-drawn vehicle. Often used in British English where American English prefers 'car'.
The train has ten passenger carriages.
We walked through every carriage on the train looking for a seat but they were all full.
The museum features a beautifully restored Victorian carriage, complete with velvet upholstery and the original crest of the family that commissioned it in the late nineteenth century.
From Middle English cariage, from Old Northern French cariage, from carier (“to carry”).
In the context of rail travel, 'carriage' is the standard British term, whereas 'car' or 'coach' is more common in North American English.