In the film franchise, the language is spoken by the Naʼvi, a race of sapient humanoids indigenous to the extraterrestrial moon Pandora.

The language was created by Paul Frommer, a professor at the USC Marshall School of Business with a doctorate in linguistics.

Naʼvi was designed to fit moviemaker James Cameron's conception of what the language should sound like in the film.

When the film was released in 2009, Naʼvi had a growing vocabulary of about a thousand words, but understanding of its grammar was limited to the language's creator.

[2] However, this has changed subsequently as Frommer has expanded the lexicon to more than 2600 words[3] and has published the grammar, thus making Naʼvi a relatively complete, learnable and serviceable language.

In 2005, while the film was still in scriptment form, Cameron felt it needed a complete, consistent language for the alien characters to speak.

His production company, Lightstorm Entertainment, contacted the linguistics department at the University of Southern California (USC) seeking someone who would be interested in creating such a language.

Based on Cameron's initial list of words, which had a "Polynesian flavor" according to Frommer,[4] the linguist developed three different sets of meaningless words and phrases that conveyed a sense of what an alien language might sound like: one using contrasting tones, one using varying vowel lengths, and one using ejective consonants.

His choice established the phonology that Frommer would use in developing the rest of the Naʼvi language – morphology, syntax, and an initial vocabulary – a task that took six months.

By the time casting for Avatar began, the language was sufficiently developed that actors were required to read and pronounce Naʼvi dialogue during auditions.

Frommer expanded the vocabulary further in May 2009 when he worked on the Avatar video game, which required Naʼvi words that had not been needed for the film script and thus had not yet been invented.

Frommer also translated into Naʼvi four sets of song lyrics that had been written by Cameron in English, and he helped vocalists with their pronunciation during the recording of James Horner's Avatar score.

Frommer also maintains a blog, Na’viteri, where he regularly posts additions to the lexicon and clarifications on grammar.

Naʼviteri has been the source of the vast majority of Naʼvi growth independent of Frommer's contract with 20th Century Fox.

Naʼvi lacks voiced plosives like [b] [d] [ɡ], but has the ejective consonants [pʼ] [tʼ] [kʼ], which are spelled px, tx, kx.

Although all the sounds were designed to be pronounceable by the human actors of the film, there are unusual consonant clusters, as in fngap [fŋap] "metal".

[8] Naʼvi syllables may be as simple as a single vowel, or as complex as skxawng "moron" or fngap above (both CCVC).

Some words include: zìsìt "year", fpeio "ceremonial challenge", ’awve "first" (’aw "one"), muiä "fair", tireaioang "spirit animal", tskxe "rock", kllpxìltu "territory", uniltìrantokx "avatar" (dream-walk-body).

The fricatives and the affricate, f v ts s z h, are restricted to the onset of a syllable; the others may occur at the beginning or at the end (though w y in final position are considered parts of diphthongs, as they only occur as ay ey aw ew and may be followed by another final consonant, as in skxawng "moron").

In final position, they have no audible release, as in Indonesian and other languages of Southeast Asia, as well as in many dialects of English in words such as "bat".

The r is flapped, as in Spanish and Indonesian; it sounds a bit like the tt or dd in the American pronunciation of the words latter / ladder.

By putting the attributive a before the adjective, the adjective can be put after the noun: Nouns in Naʼvi show greater number distinctions than those in most human languages do: besides singular and plural, they not only have special dual forms for two of an item (eyes, hands, lovers, etc.

), which are common in human language (English has a remnant in "both"), but also trial forms for three of an item, which on Earth are only found with pronouns.

For example, in the greeting in the section on nouns, Oel ngati kameie "I See you", the verb kame "to See" is inflected positively as kam⟨ei⟩e to indicate the pleasure the speaker has in meeting you.

Workarounds using existing words also abound in the Naʼvi corpus, such as eltu lefngap "metallic brain" for "computer" and palulukantsyìp "little thanator" for "cat".