Question
I’m flying to Tokyo next month and want to order water at restaurants in Japanese. I’ve heard staff say “ohiya,” but my textbook uses “reisui,” and I can’t tell which one I should actually say at the table. How do I say “Could I have cold water?” in Japanese?
Answer by Professional Japanese Teacher
お冷をください。
Ohiya o kudasai.
Could I have cold water?
At a restaurant, お冷 ohiya is the word staff use and expect to hear. It literally means “the cold one,” and in a dining context it refers to chilled drinking water served at the table. You can also soften it to ohiya o onegai shimasu — both are perfectly polite.
冷水reisui also means cold water, but it’s the bookish, written-style word. You see it on bottle labels and in health articles, rarely from a customer at a restaurant. Staff will understand you, but it sounds a little textbook-stiff.
One small tip from my classroom: water is usually served free and already chilled, so most of the time you’ll just be asking for a refill — say ohiya o kudasai with your empty glass and you’ll get one.