n. — proprietary, Food
a hot cereal mix containing cracked wheat, cracked rye and flax seeds.
Type: 1. Origin — Red River Cereal is named for the Red River which runs through the city of Winnipeg. The cereal is now produced by Smuckers, an American company, but still marketed as a Canadian product. It was first created in Manitoba in 1924 (see the Smuckers website). As Chart 1 shows, the term is most frequent in Canada.
See also COD-2, s.v. "Red River Cereal", which labels it "Cdn".
Images:

Chart 1: Internet Domain Search, 5 Oct. 2012