The greater prairie-chicken or pinnated grouse, sometimes called a boomer, is a large bird in the grouse family. This North American species was once abundant, but has become extremely rare and extirpated over much of its range due to habitat loss. Conservation measures are underway to ensure the sustainability of existing small populations. One of the most famous aspects of these creatures is the mating ritual called booming.

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.