Tillamook is an extinct Salishan language, formerly spoken by the Tillamook people in northwestern Oregon, United States. The last fluent speaker was Minnie Scovell who died in 1972. In an effort to prevent the language from being lost, a group of researchers from the University of Hawai'i interviewed the few remaining Tillamook speakers and created a 120-page dictionary.
The vowel sounds transcribed with the letters are analysed as diphthongs with increasing , being realizations of the phoneme ().
Tillamook has several phonemic "rounded" velar and uvular consonants, traditionally transcribed with the diacritic . However, this is somewhat misleading to the true phonetic articulation of these consonants, as according to Thompson & Thompson, Tillamook lacks labial elements entirely. Instead, the acoustic quality perceived as labialization is described as an internal rounding created by a "cupping" of the tongue.
This results in uvulars (postvelars) having a -like resonance, while (front) velars exhibit coloring. The chart above uses the ad hoc diacritics and to reflect this description and avoid the implication of true labialization. Similarly, the phoneme is formed with this internal rounding, making it akin to .