They recognize among themselves five main divisions, each speaking a different dialect and apparently representing as many originally distinct but cognate tribes, viz:
(1) N?kasine'na, B?achinena, or Northern Arapaho. Nakasinena, `sagebrush men,' is the name used by themselves. Baachinena, `red willow men (?),' is the name by which they were commonly known to the rest of the tribe. The Kiowa distinguished them as T?gy?ko, `sagebrush people,' a translation of their proper name. They keep the sacred tribal articles, and are considered the nucleus or mother tribe of the Arapaho, being indicated in the sign language (q. v.) by the sign for "mother people."
(2) N?wunena, 'southern men,' or Southern Arapaho, called Nawath?neha,
southerners,' by the Northern Arapaho. The Kiowa know them as ?hay?dal, the (plural) name given to the wild plum. The sign for them is made by rubbing the index finger against the side of the nose.
(3) A?'ninena, Hit?nena, atsina, or Gros Ventres of the Prairie. The first name, said to mean `white clay people,' is that by which they call themselves. Hit?nena, or Hittiuenina, 'begging men,' `beggars,' or more exactly 'spongers,'' is the name by which they are called by the other Arapaho. The same idea is intended to be conveyed by the tribal sign, which has commonly been interpreted as `big bellies,' whence the name Gros Ventres applied to them by the French Canadians. In this way they have been by some writers confused with the Hidatsa, the Gros Ventres of the Missouri.
(4) B?sawunena, ' wood-lodge people,' or, possibly, ' big lodge people.' These, according to tradition, were formerly a distinct tribe and at war with the Arapaho, but have been incorporated for at least 150 years. Their dialect is said to have differed considerably from the other Arapaho dialects. There are still about 50 of this lineage among the Northern Arapaho, and perhaps a few with the other two main divisions.
(5) H?nahawuuena (`rock men' Kroeber) or Aan?'nhawa. These, like the B?sawunena, lived with the Northern Arapaho, but are now practically extinct.

The two main divisions, Northern and Southern, are subdivided into several local bands, as follows:
(a) Forks of the River Men
(b) Bad Pipes
(c) Greasy Faces, among the Northern Arapaho;
(d) W?quithi, bad faces,
(e) Ag?thine'na, pleasant men,
(f) Gawunena, Blackfeet, said to be of Siksika admixture;
(g) H?qihana, wolves,
(h) S?st?b?ithi, looking up, or looking around, i. e., watchers.