diner

Short definition from Wiktionary

Noun

1. 1
   One who dines.
2. 2
   One who gives a dinner.
3. 3
   A dining car in a railroad train.
4. 4
   A typically small restaurant, historically 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.
5. 5
   A commemorative currency of Andorra, not legal tender, divided into 100 centims.