As part of the Yuman family, Tiipai has also been consistently included in the controversial quasi-stock Hokan.
However, linguists now recognize that they represent at least three distinct language clusters within a speech variety continuum.
[3][6] Tiipai itself is not a uniform speech variety, with borders that are far from clearcut and variations across towns such as Jamul, San José, and La Huerta.
[6] Published documentation of the Tiipai language includes a descriptive grammar of Jamul Tiipai,[6] a trilingual dictionary,[10] a trilingual book of stories and oral histories from Baja California Kumiai communities,[11] a word list,[12] and texts, including audio and video on the ELAR website.
Only predictable variations are discussed below, but there are additional cases where two allophones covary, appearing in the same condition.
Analysis of the term is complicated, so since the phoneme is only found in one native word, /b/ is not included in the above table.
[6] As is typical of other Yuman languages, Tiipai words contain a singular stressed syllable, always corresponding to the grammatical root.
The glottal stop /ʔ/ is only found in stem-initial or root-initial positions, or immediately proceeding a root, where it is followed by a stressed phoneme.
[6] Roughly six major rules governing phonemic sound changes have been posited in Tiipai, listed below.
Note that /e/ deletion may occur in other environments to restore initial and medial clusters, but since this behavior is not fully regular, it is not described as a rule below.
In 17 instances, full reduplication occurs, with the stress falling on the second syllable: chilchil "to be too tight (clothing)".
In 5 instances, full reduplication occurs except the vowel of the first syllable is reduced to /e/: kellykully "to peek in".
For all derivational processes in Tiipai, there are several morphemes that, unless indicated otherwise, can each independently and optionally express their corresponding morphological function.
Distributive action verbs are formed similarly, except the only processes that may occur include prefixation of ch-, suffixation of -ch, and root vowel length change.
Finally, there exist special person prefixes for relative clauses in the subject position: Albeit much less than verbs, nouns also bear some morphology in Tiipai.
Interestingly, noun pluralization actually closely resembles the causative, but with only the prefixes ch- and aa- accompanying suffixes -ch and -a and root vowel length change.
Inalienable possession applies to body parts, some items of clothing, pechaay "daughter (man's term)", aa "language", shiimull "tribe, last name", and keyaw "behalf".
They inflect similarly, except with the additional prefix ny- appearing after the person affixes: menya'naak "your chair".
The following markings indicating case are suffixed to the end of the noun phrase: [6] The default word order of Tiipai is (S)(O)V. Overt expression of nouns is optional and functions only to specify or "lexicalize", as person for subjects and objects is marked on the verb, as discussed above.
There is also a demonstrative clitic -pu, often used more for textual deixis or marking the ends of complex noun phrases.
These suffixes are cliticized to the dependent clause verb, and can express simultaneous or sequential events.