Largest of the green-pigeons, a stout-billed, heavy-chested, and broad-winged bird. Male olive-green overall, washed in gray, with small orange patch on chest. Orange-breasted and Pink-headed Green-Pigeons are smaller, brighter green, and have other colorful patches on the body. Female similarly colored but with paler, smaller orange patch; much larger than other green-pigeons. Gives groaning, undulating coos.