[noun] [C]A diner is someone who is eating a meal, esp. in a restaurant.(US) A diner is a (small) restaurant at the side of the road, esp. one with a long table at which people sitting in fixed seats are served, and with the appearance of the part of a train in which passengers are served meals.
DINER
Meaning of DINER in English
Cambridge English vocab. Кембриджский английский словарь. 2012