Great tinamou are approximately 44 cm (17 in) long, 1.1 kg (2.4 lb) in weight and size and shape of a small turkey. It ranges from light to dark olive-green in colour with a whitish throat and belly, flanks barred black, and undertail cinnamon. Crown and neck rufous, occipital crest and supercilium blackish. Its legs are blue-grey in colour. All these features enable great tinamou to be well-camouflaged in the rainforest understory. The great tinamou has a distinctive call, three short, tremulous, but powerful piping notes which can be heard in its rainforest habitat in the early evenings.