Akitian language

The Akitian language (秋津語, Akitugu) is one of the two official languages of Akitsu. It is classified as part of the Japonic language family, alongside Japanese and the Ryukyuan languages.

Phonology
Akitian phonology is extremely similar to Japanaese phonology. Things shared by Akitian and Japanese include a voicing opposition for obstruents, CV(C) syllable structure, moraic rhythm, and pitch accent. Akitian vowels are even identical to Japanese vowels. However, Akitian does have differences from Japanese. For example, the voiceless bilabial fricative, the "f" sound in English which is also present in Japanese, is not present in Akitian. The "t͡s" sound is also not present in Akitian. Also, some Akitian words have a glottal stop, something not common in Japanese.

However, while Akitian phonology is extremely similar to Japanese, Akitian phonotactics are more similar to Ryukyuan.

Grammar
Grammatically, Akitian is more similar to Okinawan than to Japanese. For example, like Okinawan but unlike Japanese, Akitian distinguishes between terminal forms and attributive forms. That said, Akitian isn't identical to Okinawan either. Akitian has clusivity for first-person pronouns, unlike both Japanese and Okinawan.