Chiwere (also called Iowa-Otoe-Missouria or Báxoje-Jíwere-Ñútˀachi) is a Siouan language originally spoken by the Missouria, Otoe, and Ioway peoples in Northeast Kansas and parts of Missouri and Nebraska. The language is closely related to Ho Chunk (Winnebago).
The name by which the Ioways refer to their language is Báxoje ichˀé or Bah Kho Je (). The Otoe-Missouria dialect is called Jíwere ichˀé (). The spelling Chiwere, used mostly by linguists, derives from the fact that the language has an aspiration distinction rather than a voice distinction, so that the unaspirated stops [b d j g] are sometimes heard as [p t ch k] by speakers of other languages. Although is a valid pronunciation of the first sound of Jiwere ~ Chiwere, it may mislead some people into pronouncing this consonant . Similarly, a common folk etymology of Báxoje is "dusty noses", based on the misunderstanding of the first syllable bá as pá, or "nose".
Today, Chiwere is only spoken by a very few elder people within the tribal communities of the Otoe-Ioway in Oklahoma and Missouri . The only dialect spoken today is the Ioway dialect. The last fluent speaker of the Otoe-Missouria variety was Truman Washington Dailey (Eagle clan name: Mashi Manyi, man name: Sunge Hka) who died in 1996.
Christian missionaries first documented Chiwere in the 1830s, though since then there has been virtually nothing published about the language. Chiwere suffered a steady decline after European colonization in the 1850s, and by 1940 the language had almost totally ceased to be spoken.
Currently, Chiwere is highly endangered. With the last two fluent speakers dying in the Winter of 1996, only a handful of semi-fluent speakers remain, all of whom are elderly. Although the Otoe-Ioway people themselves have no Chiwere learning programs, a few external sources are working to preserve the language into the next decade. In spite of these efforts, it is likely that Chiwere will become extinct in the very near future.