A typically small restaurant, usually modeled after a railroad dining car, that serves lower-class fare, normally having a counter with stools along one side and booths on the other, and often decorated in 50s and 60s pop culture themes and playing popular music from those decades.
One who dines.
A dining car in a railroad train.
An eating establishment in which diners are served food, usually by waiters at their tables but sometimes (as in a fast food restaurant) at a counter.