|Native to||West Papua, Indonesia|
|Region||Inanwatan District, South Sorong Regency in the Bird's Head Peninsula|
Inanwatan is a Papuan language of West Papua. It is often classified in the South Bird's Head language family, but may alternatively form an independent language family together with Duriankere.
Inanwatan is primarily spoken in the village of Inanwatan, South Sorong Regency on the south coast of the Bird's Head Peninsula, but also in the village of Seget, Sorong Regency on the western tip of the peninsula, as well as by a community in the Jalan Ferry area of the city of Sorong.
Inanwatan is endangered: de Vries reports in 2004 that it was mostly people over 50 years of age who speak it fluently, and that the newest generation do not know it. According to his estimate, Inanwatan has 800 or fewer speakers, out of an ethnic population of about 3,000. The language is not a central component of the identity of the people, who identify more strongly with the smaller descent groups.
The language is also known under the names Bira, Suabo, Iagu and Mirabo,[better source needed] while the Inanwatan themselves most commonly refer to it as nidáibo 'our language'. It is most closely related to the Duriankari language.
Like the Romance languages, Inanwatan distinguishes masculine and feminine grammatical genders. Inanwatan masculine nouns end in the front vowels -i and -e, and feminine nouns end in non-front vowels -u, -o, -a. Maybrat, on the other hand, uses concord prefixes instead of suffixes to mark gender.
Inanwatan nouns usually have lexically determined gender, but some of the nouns allow for choice of gender via varying gender suffixes:
Inanwatan feminine forms are homophonous with plural forms, while masculine forms are distinct.