Yidiny forms a separate branch of Pama–Nyungan. It is sometimes grouped with Djabugay as Yidinyic, but Bowern retains Djabugay in its traditional place within the Paman languages.
Sounds
Vowels
Yidiny has the typical Australian vowel system of /a, i, u/. Yidiny also displays contrastive vowel length.
Consonants
Yidiny consonants, with no underlyingly voiceless consonants, are posited. It is not clear if the two rhotics are trill and flap, or tap and approximant. Dixon gives them as a "trilled apical rhotic" and a "retroflex continuant".
Grammar
The Yidiny language has a number of particles that change the meaning of an entire clause. These, unlike other forms in the language, such as nouns, verbs and gender markers, have no grammatical case and take no tense inflections. The particles in the Yidiny language: nguju - 'not', giyi - 'don't', biri - 'done again', yurrga - 'still', mugu - 'couldn't help it', jaymbi / jaybar - 'in turn'. E.g. 'I hit him and he jaymbi hit me', 'He hit me and I jaybar hit him'. Dixon states that "pronouns inflect in a nominative-accusative paradigm… deictics with human reference have separate cases for transitive subject, transitive object, and intransitive subject… whereas nouns show an absolutive–ergative pattern." Thus three morphosyntactic alignments seem to occur: ergative–absolutive, nominative–accusative, and tripartite.
Pronouns and deictics
Pronoun and other pronoun-like words are classified as two separate lexical categories. This is for morphosyntactic reasons: pronouns show nominative-accusative case marking, while demonstratives, deictics, and other nominals show absolutive-ergative marking.
Affixes
In common with several other Australian Aboriginal languages, Yidiny is an agglutinativeergative-absolutive language. There are many affixes which indicate a number of different grammatical concepts, such as the agent of an action, the ablative case, the past tense and the present and future tenses. There are also two affixes which lengthen the last vowel of the verbal root to which they are added, -Vli- and -Vlda. For example: magi- 'climb up' + ili + -nyu 'past tense affix', magi- 'climb up' + ilda + -nyu 'past tense affix'. The affix -Vli- means 'do while going' and the affix -Vlda- means 'do while coming'. It is for this reason that they cannot be added to the verbs gali- 'go' or gada- 'come'. Therefore, the wordmagiilinyu means 'went up, climbing' and magiildanyu means 'came up, climbing'. One morpheme, -ŋa, is an applicative in some verbs and a causative in others. For example, maŋga- 'laugh' becomes applicative maŋga-ŋa- 'laugh at' while warrŋgi- 'turn around' becomes causative warrŋgi-ŋa- 'turn something around'. The classes of verbs are not mutually exclusive however, so some words could have both meanings, which are disambiguated only through context.
Affixes and number of syllables
There is a general preference in Yidiny that as many words as possible should have an even number of syllables. It is for this reason that the affixes differ according to the word to which they are added. For example: the past tense affix is -nyu when the verbal root has three syllables, producing a word that has four syllables: majinda- 'walk up' becomes majindanyu in the past tense, whereas with a disyllabic root the final vowel is lengthened and -Vny is added: gali- 'go' becomes galiiny in the past tense, thus producing a word that has two syllables. The same principle applies when forming the genitive: waguja- + -ni = wagujani 'man's', bunya- + -Vn- = bunyaan 'woman's'. The preference for an even number of syllables is retained in the affix that shows a relative clause: -nyunda is used with a verb that has two or four syllables, giving a word that has four syllables whereas a word that has three or five syllables takes -nyuun, giving a word that has four syllables.
Some words
bunggu. 'Knee,' but more extensively: 'That part of the body of anything which, in moving, enables the rest of the body or object to be propelled.' This is used of the hump in a snake's back as it wriggles, the swish point of a crocodile's tail, or the wheel of a car or tractor.
jilibura. 'Green ant'. It was squeezed, and the 'milk' it yielded was then mixed with the ashes of a gawuul, or from a murrgan or a bagirram tree, and the concoction then drunk to clear headaches. The classifier used for ants,munyimunyi was used for all species, such as the gajuu and burrbal,, but never for a jilibura because it was different, having a medicinal use.
