Kagu name "Rhynochetos", and the clade name Rhynochetidae, are derived from the Greek "rhis" meaning nose and "chetos" meaning corn, referring to the corn-shaped flaps over the nostrils. The specific name "jubatus" is derived from the Latin "iabatus" meaning crested. The name kagu is derived from the Melanesian names for the species. The species is variously known as the "kavu" or "kagou" in the Kanak languages, and as the "cagou" in French (also used as an alternative spelling in English). The kagu is a ground-living bird, in length. The weight can vary considerably by individual and by season, ranging from .
Kagu have been found on the Ile des Pines. The kagu is a habitat generalist and able to exist in a range of different forest types if sufficient prey is present, from rain forest to drier lowland forest. They are also able to feed in some drier shrubland associated with the island's ultrabasic rocks, although not in the low-prey, poor shrubland of this type. They are also absent from areas where extensive ground cover makes foraging difficult, such as grassland or areas with high fern cover, but may pass through such areas to reach other foraging areas. The species has undergone