In railroading, an ordinary passenger-ear with ordinary double seats, as distinguished from a sleeping-car, drawing-room ear, dining-car, or chair-car: not necessarily limited to day use.(noun)
The Century Dictionary (Public Domain)
Use "day-coach" in a sentence
"He was beside her on the red plush seat of the day-coach; a boy of three and a half."
"In the shelter of an ancient, grimy day-coach, the scum muttered again, as Smith brushed past him in the aisle."
""Across the continent in a day-coach, I suppose," laughed Hortense, yawning."