The Papuan languages are those languages of the western Pacific that are neither Austronesian nor Australian. The term does not presuppose a genetic relationship. The concept of Papuan peoples as distinct from Melanesians was first suggested and named by Sidney Herbert Ray in 1892.
New Guinea is perhaps the most linguistically diverse region in the world. Besides the Austronesian languages, there are some 800 languages divided into perhaps sixty small language families, with unclear relationships to each other or to anything else, plus a large number of language isolates. The majority of the Papuan languages are spoken on the island of New Guinea, with a number spoken in the Bismarck Archipelago, Bougainville Island, and the Solomon Islands to the east, and in Halmahera, Timor, and the Alor archipelago to the west. The westernmost language, Tambora in Sumbawa, is extinct. One Papuan language, Meriam Mir, is spoken within the national borders of Australia, in the eastern Torres Strait. The only Papuan languages with official recognition are those of East Timor.
Several languages of Flores, Sumba, and other islands of eastern Indonesia are classified as Austronesian but have large numbers of non-Austronesian words in their basic vocabulary and non-Austronesian grammatical features. It has been suggested that these may have originally been non-Austronesian languages that have borrowed nearly all of their vocabulary from neighboring Austronesian languages, but no connection with the Papuan languages of Timor has been found. In general, the Central–Eastern Malayo-Polynesian languages are marked by a significant historical Papuan influence, lexically, grammatically, and phonologically, and this is responsible for much of the diversity of the Austronesian language family.
Most Papuan languages are spoken by hundreds to thousands of people; the most populous are found in the New Guinea highlands, where a few exceed a hundred thousand. These are Western Dani (180,000) and Ekari (100,000) in the western (Indonesian) highlands, and Enga (165,000) and Melpa (130,000) in the eastern (PNG) highlands. To the west of New Guinea, the largest languages are Galela in Halmahera (80–95,000) and Makasai in East Timor (70,000). To the east, Terei (27,000) and Naasioi (20,000) are spoken on Bougainville.
Although there has been relatively little study of these languages compared with the Austronesian family, there have been three preliminary attempts at large-scale genealogical classification, by Joseph Greenberg, Stephen Wurm, and Malcolm Ross. The largest family posited for the Papuan region is the Trans–New Guinea phylum, consisting of the majority of Papuan languages and running mainly along the highlands of New Guinea. The various high-level families may represent distinct migrations into New Guinea, presumably from the west. Since perhaps only a quarter of Papuan languages have been studied in detail, linguists' understanding of the relationships between them will continue to be revised.