The voiceless alveolar bilabially trilled affricate, [t̪͡ʙ̥] (occasionally written "t^p"), is one of the world's rarest sounds. It is reported from a few words in the Chapacuran languages, Wari’ and Oro Win, and recently also from the neighboring Muran language Pirahã. The sound also appears as an allophone of the labialised voiceless alveolar plosive /tʷ/ of Abkhaz and Ubykh, but in those languages it is more often realised by a doubly articulated stop [t͡p].

[tʙ̥] is considered to be a single consonant in these Amazonian languages because they do not otherwise have bilabial trills or consonant clusters. This is a stronger version of the argument made for [dʒ] being a single sound in English.

[tʙ̥] will regularly be trilled with three contact oscillations, as is normal for alveolar trills. However, trills are occasionally pronounced as fricatives in many languages, especially in slurred speech. When this happens to [tʙ̥], it is pronounced [tpɸ].

In the Chapacuran languages at least, [tʙ̥] is reported almost exclusively before rounded vowels. This probably has something to say about the development of this sound.

In Wari’ the sound is only known from two dozen words. A few of these are:

References

External links

• Oro Win recordings