Definition of "mirin"

Although naturally brewed mirin is made from only water, sweet brown rice, and rice koji, much of the mirin sold in natural food stores and Oriental markets is sweetened with sugar or corn syrup; read labels carefully.

1989 November, Drew DeSilver, Jan Gahala, “What is that stuff?”, in Vegetarian Times, page 43

Teriyaki sauce, a mixture of mirin, sake, soy sauce, and sometimes sugar, may be brushed on meats, fish, or vegetables […]

2017, James Peterson, Sauces: Classical and Contemporary Sauce Making, HarperCollins