Both in ethnic population and in number of speakers, the Central Alaskan Yupik people form the largest group among Alaska Natives.

Yupʼik, like all Eskimo languages, is polysynthetic and uses suffixation as primary means for word formation.

There are a great number of derivational suffixes (termed postbases) that are used productively to form these polysynthetic words.

The variety of Yup'ik spoken by the younger generations is being influenced strongly by English: it is less synthetic, has a reduced inventory of spatial demonstratives, and is lexically Anglicized.

[8][11][12] All extant dialects of the language are mutually intelligible, albeit with phonological and lexical differences that sometimes cause difficulty in cross-dialectal comprehension.

[11][13] Lexical differences exist somewhat dramatically across dialects, in part due to a historical practice of name taboo.

The following table compares some words in two sub-dialects of General Central Yupʼik (Yugtun).

[16] Early linguistic work in Central Yupʼik was done primarily by Russian Orthodox, then Jesuit and Moravian Church missionaries, leading to a modest tradition of literacy used in letter writing.

Their work led to the establishment of the state's first bilingual school programs in four Yupʼik villages in the early 1970s.

Since then a wide variety of bilingual materials has been published, including Steven Jacobson's comprehensive dictionary of the language, his complete practical classroom grammar, and story collections and narratives by many others including a full novel by Anna Jacobson.

Consonants may also occur long (geminate), but their occurrence is often predictable by regular phonological rules, and so in these cases is not marked in the orthography.

The voiceless labialized uvular fricative [χʷ] occurs only in some speech variants and does not contrast with its voiced counterpart /ʁʷ/.

For example, /tʃali-vig-∅/ "work-place-ABS" is pronounced [tʃaliːwik] (orthographically, calivik), since /v/ occurs between two full vowels and it not adjacent to the inflectional suffix.

[8] In Norton Sound, as well as some villages on the lower Yukon, /j/ tends to be pronounced as [z] when following a consonant, and geminate /jː/ as [zː].

For example, the word angyaq "boat" of General Central Yup'ik (GCY) is angsaq [aŋzaq] Norton Sound.

[12][8] Conversely, in the Hooper Bay-Chevak (HBC) dialect, there is no /z/ phoneme, and /j/ is used in its place, such that GCY qasgiq [qazɣeq] is pronounced qaygiq [qajɣeq].

[12] Occasionally these assimilation processes do not apply, and in the orthography an apostrophe is written in the middle of the consonant cluster to indicate this: at'nguq is pronounced [atŋoq], not [atŋ̊oq].

In this word the second, fourth, and sixth syllables are pronounced with long vowels as a result of iambic lengthening.

[12][8] Because the vowel /ə/ cannot occur long in Yup'ik, when a syllable whose nucleus is /ə/ is in line to receive stress, iambic lengthening cannot apply.

The first of these is often called the stem (equivalent to the notion of a root), which carries the core meaning of the word.

Following the stem come zero or more postbases,[12] which are derivational modifiers that change the category of the word or augment its meaning.

The third section is called an ending, which carries the inflectional categories of case (on nouns), grammatical mood (on verbs), person, and number.

[20] Finally, optional enclitics may be added, which usually indicate "the speaker's attitude towards what he is saying such as questioning, hoping, reporting, etc.

[8] Identifies the definite object of a transitive verb Marks nominals demoted from absolutive case under valency reduction (none) Marks nominals demoted from relative case under valency reduction (none) Indicates the standard of comparison in comparatives than co-occurs with the verb ayuqe- "resemble" The forms of these grammatical cases are variable, depending on the grammatical person and number of the head noun as well as the person and number of its possessor (if there is one).

The two leftmost nouns below are unpossessed, but the third is marked for a first person singular possessor -ka (pronounced in this case as -qa after assimilating to a uvular place of articulation).

For example, the English sentence The dog bit the preacher means something different than The preacher bit the dog does; this is because in English, the noun that comes before the verb must be the agent (the biter), while the noun following the verb must be the theme (the individual or thing that is bitten).

This obtains, for instance, when both arguments of an indicative transitive verb are third person plural and unpossessed: elitnauristet mikelnguut assikait can, in principle, mean either "the teachers like the children" or "the children like the teachers", since the case marking on elitnauristet "teachers" and mikelnguut "children" does not distinguish ergative from absolutive case (-t marks unpossessed ergative plurals as well as unpossessed absolutive plurals).

This twelve-way contrast is cross-cut by a trinomial contrast in horizontal extension/motion: this determines whether the referent is extended (horizontally long or moving) or non-extended, and if non-extended, whether distal (typically far away, indistinct, and invisible) or proximal (typically nearby, distinct, and visible).

To illustrate, the spatial demonstrative roots of Yup'ik (which are then inflected for case and number) are presented in the following table from Miyaoka (2012).

[28] Then, during the mid-1970s, educational programs emerged in order to revive and sustain the Yupʼik language: MacLean notes that "In 1975, an Alaska State statute was enacted directing all school boards to '...provide a bilingual-bicultural education program for each school...which is attended by at least 8 pupils of limited English-speaking ability and whose primary language is other than English'".