Definition from Wiktionary, the free dictionary
lunchroom (plural lunchrooms)
- A room reserved for eating food, especially at a business (lunch may or may not be served there).
- We made a point to eat in the lunchroom, not at our desks.
- A diner or restaurant that specializes in serving lunch.
- I don't know how they stay in business serving only lunch, but the lunchroom on the corner is cheap and fast so I like it.