Is this your crossword clue?
"diner" is also used as a crossword clue. If that's what you saw, the answer is often eater (5 letters).
Definitions
Casual restaurant, often resembling a railway dining car.
Word origin
From dine + -er.
Used in a sentence
“Pacific No. 60123, H. A. Ivatt, a Leeds engine with 12 corridors, but no diners, went by, however.”
“The diner is everybody's kitchen.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Roadside eatery”5 letters
Not quite right?
"Search similar patterns."
D____