Grouse are a group of birds from the order Galliformes, in the family Phasianidae. Grouse are presently assigned to the tribe Tetraonini, a classification supported by mitochondrial DNA sequence studies, and applied by the American Ornithologists' Union, ITIS, International Ornithological Congress, and others.

Galliformes is an order of heavy-bodied ground-feeding birds that includes turkeys, chickens, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems as seed dispersers and predators, and are often reared by humans for their meat and eggs, or hunted as game birds.