"dish room" is correct and usable in written English.
You could use it when referring to a room used for cleaning dishes. For example: "The dish room is located just off the kitchen."
The loud jets of the steamer had shut off automatically and the dish room grew quiet.
You wouldn't believe what people could do with food until you worked in a dish room.
"Whatever you do, don't work in a dish room ever again.
We hosed the dish room, the kitchen, the serving line, sending the water and crud and suds into the drains.
I think I began to love Heidi that night in the dish room, but who is to say that I hadn't begun to love her the first time I met her?
Three managers sat at my table and sent me to the dish room to load up: ice bowl, strawberry tray, eight Champagne flutes and a wine stand all in one trip.
On the third floor, the apartment consisted of eight residential rooms, a foyer, a kitchen, dish washing room, two rooms for servants, a bathroom, and two toilets.
Frat boys arrived at the dish-room window, en masse.
If you tried to prize them off, milk, Worcestershire sauce, peas, chunks of bread vomited onto your dish-room uniform.
Though I was the one who'd broken away after she went up to that podium, I still half expected her to poke her head out a window in Linsly-Chit, or tap on my back in Harkness, or even join me in the Commons dining hall, where I'd asked for my dish-room shift to be transferred.
Complete media were then added to the polystyrene dish at room temperature to inhibit the effects of trypsin.
