Iwi (Māori pronunciation: [ˈiwi]) are the largest social units in New Zealand Māori society. In Māori, iwi roughly means 'people' or 'nation', and is often translated as "tribe". The word is both singular and plural in the Māori language, and is typically pluralised as such in English.
Iwi groups trace their ancestry to the original Polynesian migrants who, according to tradition, arrived from Hawaiki. Some iwi cluster into larger groupings that are based on whakapapa (genealogical tradition) and known as waka (literally 'canoes', with reference to the original migration voyages). These super-groupings are generally symbolic rather than logistical. In pre-European times, most Māori were allied to relatively small groups in the form of hapū ('sub-tribes') and whānau ('family'). Each iwi contains a number of hapū; among the hapū of the Ngāti Whātua iwi, for example, are Te Uri-o-Hau, Te Roroa, Te Taoū, and Ngāti Whātua-o-Ōrākei. Māori use the word rohe for the territory or boundaries of iwi.