Timothy Usher, Santa Fe Institute
Dibiyaso, also known as Bainapi, is spoken by approximately 400 people (1976) living in three villages in the lowlands north of the Aramia river, east of the Soari river and west of the upper Bamu river and Wawoi rivers, in Papua New Guinea's Western Province. They moved from a location to the north ,west of the Wawoi, to their current location on the Aramia sometime around 1941. According to Reesink, each village has a different name for the language: in Makapa it is called Turumasa, in Pikiwa it is called Bainapi and in Bamustu it is Dibiasu. Bainapi is said to be a clan name (Reesink 1976: 11.)
Rentoul (1924-1925: 74 ) 39 comparative terms for Dibiasu
Franklin (ed. 1973: 559) 47 comparative terms for Bainapi
Shaw (1986: 69) 99 comparative terms for Bainapi
Reesink (1976: 11-12) comparative notes on and (pp. 31-34) 97 comparative terms for Bainapi
Rueck, MacKenzie and Alemán (2005: 8-20) 156 comparative terms for Dibiyaso of Bamustu, Makapa and Pikiwa villages after MacKenzie and Carr
Reesink (1976: 13) gives 12 consonants and 7 vowels for Bainapi as follows:
| m | n | ||
| p | t | k | |
| b | d | g | |
| f | s | ||
| w | j |
| i | u | |
| e | o | |
| ɛ | ɔ | |
| a |
At least eight vowel sequnces are found as follows:
| i | u | e | a | |
| i | — | — | — | ia |
| u | — | — | — | ua |
| e | ei | — | — | ea |
| o | — | ou | — | — |
| a | ai | au | ae | — |
The vowels of stressed syllables are lengthened. Stress is likely phonemic.
Rueck, MacKenzie and Alemán (2005: 19-20 after MacKenzie) give pronouns for Dibyaso of Makapa village and Reesink (1976: 31, Shaw 1986: 69) for Bainapi as follows:
| MacKenzie | Reesink | |
| 1 sg. | na'ne | nanɛ |
| 2 sg. | ga'ge | gagɛ |
| 3 sg. | 'ene | ? |
| 1 pl. | nini | nini |
| 2 pl. | 'gigi | ? |
| 3 pl. | 'ini | ? |
No information about Dibiyaso verbal morphology is available to us.