|Cobourg Peninsula region, Northern Territory|
|Linguistic classification:||Arnhem Land?
Iwaidjan languages (purple), among other non-Pama-Nyungan languages (grey)
Closeup. Amurdag is the southern section (tan), Wurrugu the tip of the peninsula (green), the rest Iwaidjic (purple). On the grey island just offshore is Marrgu, once thought to be Iwaidjan.
The Iwaidjan languages 
Dixon (2002) considers Warrkbi demonstrated, but Iwaidjic (Warrkbi-Maung) and Iwaidjan to be speculative. He predicts that working out the histories of the languages will be a "profound challenge", regardless of whether they are a genealogical family or a language area.
Marrgu, previously thought to be Iwaidjan, may turn out to be a language isolate.
Iwaidja is spoken by about 150 people in the community of Minjilang on Croker Island, alongside English, Kunwinjku and Maung. Maung is primarily spoken in the community of Warruwi on Goulburn Island, and it too has about 150 speakers. Both languages are still being learnt by children.
All the other Iwaidjan languages are close to extinction. In 1998[update], Amurdak had three remaining speakers, Garig and Ilgar three speakers between them, Marrgu one speaker, and Wurrugu one rememberer.
The Iwaidjan languages have similar phoneme inventories. Exceptions are noted below the tables.
|Lateral flap||ɺ||ɺ˞ |
To these Marrgu adds a lamino-dental stop and nasal, /d̪ n̪/, while Maung lacks the two flapped laterals, which are quite unusual among Australian languages. Also unusual is the velar approximant /ɰ/, which is an areal feature shared with Tiwi and Kunbarlang.
Relationships with other languages 
The vocabularies of all the Iwaidjan languages contain loanwords from Macassarese and Malay, both Malayo-Polynesian languages from Indonesia. Iwaidja and Maung have also borrowed heavily from Kunwijku, another Australian language of the Gunwingguan family.
While the Iwaidjan languages share a number of features with other non-Pama–Nyungan language families, it is uncertain which they are closest related to. Ross has proposed that they form part of an Arnhem Land family.
- Bowern, Claire. 2011. How Many Languages Were Spoken in Australia?
- Evans (1998): pp. 115, 144.
- Evans (1998): pp. 115–116.
- Evans (1998): p. 115
- Evans (1998): p. 118.
- There is no standard IPA symbol for a retroflex lateral flap. is sometimes seen, or ɭ̆.
- Evans (1998): p. 117.
- Evans (1998): p. 116.
- Evans, Nicholas (1998). "Iwaidja mutation and its origins". In Anna Siewierska & Jae Jung Song. Case, Typology and Grammar: In honor of Barry J. Blake. Amsterdam/Philadelphia: John Benjamins Publishing Company. pp. 115–149.