In This Article Expand or collapse the "in this article" section Language Isolates

  • Introduction
  • General Overviews and Edited Volumes
  • Issues in Classification
  • Language Isolates in Historical Perspective
  • Language Isolate Geography

Linguistics Language Isolates
Mattias Urban
  • LAST REVIEWED: 12 January 2023
  • LAST MODIFIED: 12 January 2023
  • DOI: 10.1093/obo/9780199772810-0299


Language isolates, or alternatively isolated languages, are languages for which it has not, or not yet, been possible to establish genealogical connections. A language isolate therefore forms a self-contained language family (in the sense of a phylum or a lineage) of which it is the only known member. The qualifier “not yet” is necessary because the comparative method of historical linguistics, which is used to demonstrate such connections, can only prove that languages are genealogically related, never that they are not. Therefore, it is always possible that a language isolate may eventually lose that status if successfully connected genealogically to other languages. The extent of research that has been carried out to do so varies drastically from language isolate to language isolate; Basque is probably among the language isolates for which most effort has been invested, though without leading to evidence that would satisfy all or even just the majority of specialists. On the other hand, the genealogical status of a language that had been previously assigned to a family may be reconsidered at a later, more mature state of research. In the course of such reevaluations, it may be found that evidence for the classification has been insufficient, which necessitates removing that language from the family and assigning it isolate status for the time being. This in fact happened in the case of Basque, which at an earlier state of research had been thought to form a family with the extinct so-called Iberian language (however, given the definition above with the qualifier “the only known member,” a language that is the sole survivor of a once-larger family whose relatives have ceased to be spoken is usually not labeled language isolate). There are around 150–200 languages that may be considered language isolates. Stating a more precise figure is difficult and of little scientific interest, for several reasons. One is the evolving nature of language classification just mentioned. Another has to do with the poor state of documentation of some extinct languages, especially in the former colonial world. In such cases, available materials may be insufficient to classify the language (however, there are no hard-and-fast rules as to how much is sufficient, and there is therefore no sharp boundary between languages that are unclassifiable for lack of documentation and a language isolate). The other reason is more properly linguistic: like any other language, a language isolate may be dialectally diverse, and if that diversification continues, it will eventually turn into a language family. Huave, a language isolate of Mexico, for instance, is now more commonly treated as a small Huavean language family of closely related languages.

General Overviews and Edited Volumes

For scholars interested in a quick overview of languages that may be considered isolates and extant linguistic work on these (as well as sometimes ethnographic work on its speakers), Glottolog 4.6 (see Hammarström, et al. 2022) is highly recommended. On the “Families” tab, the value “Isolate” can be selected in the column “Level” to display all 182 languages Glottolog 4.6 classifies as isolates. This is a mostly conservative classification that tends to not follow “lumping” tendencies unless solid and extensive evidence is available; note though that Glottolog also features a number of “unclassifiable” languages that some may consider language isolates (see Introduction and Issues in Classification). Another source on the languages of the world that allows to search for language isolates is the Ethnologue (see Eberhard, et al. 2022). A list of endangered language isolates, which according to the authors’ count includes 86 of the total of approximately 159 listed in Campbell 2018a, can be found in Barlow and Campbell 2018 (pp. 36–41). Georg 2015 and Campbell 2018b are two edited volumes on language isolates. Georg 2015 is a four-volume collection of previously published papers on language isolates that are either overview sketches or deal with more specific topics. Having appeared in Routledge’s “Language Family” series, Campbell 2018b features an introductory chapter by the editor himself (Campbell 2018a) that provides an overview of the 159 isolates he recognizes and that also summarizes approaches to exploring the history of language isolates. The volume features chapters on some particularly well-studied isolates, and overviews of the isolates of other regions on the world (see also Campbell 2010). Reflecting the differences in research done on individual isolates (see Introduction), coverage is uneven, but the volume is highly useful and suitable as the principal starting point for research on individual language isolates.

  • Barlow, R., and L. Campbell. 2018. Language classification and cataloguing endangered languages. In Cataloguing the world’s endangered languages. Edited by L. Campbell and A. Belew, 23–48. Abingdon, UK, and New York: Routledge.

    Dealing with language classification and endangered languages generally, this chapter also has a section on endangered language isolates. Classification is consistent with Campbell 2010 and Campbell 2018a so that these works can be read in a complementary fashion.

  • Campbell, L. 2010. Language isolates and their history, or, what’s weird, anyway? Berkeley Linguistics Society 36: 16–31.

    DOI: 10.3765/bls.v36i1.3900

    A precursor to Campbell 2018a, this article covers much the same topics as the later chapter. This includes the definition of language isolates, the associated question of “unclassified” languages and extinct relatives, the number of language isolates in the world, and how language isolates can be put into a historical perspective. The general position Campbell advocates is that language isolates do not differ significantly from non-isolate languages along several parameters.

  • Campbell, L. 2018a. Language isolates and their history. In Language isolates. Edited by L. Campbell, 1–18. Abingdon, UK, and New York: Routledge.

    A slightly updated version of Campbell 2010 that serves as an introduction to Campbell 2018b. Like its precursor, the text provides a definition of language isolates that takes into account the problem of “unclassified languages” and extinct relatives, the question of how many language isolates there are, and possibilities for historical research on language isolates.

  • Campbell, L., ed. 2018b. Language isolates. Abingdon, UK, and New York: Routledge.

    Features an introduction and chapters on language isolates of Europe and the Ancient Near East, Basque, Ainu, Burushaski, and area-based surveys of language isolates in Asia, Africa, North America, Mesoamerica and Northern Mexico, South America, New Guinea, and Australia. The volume is rounded off by a chapter on the endangerment of language isolates.

  • Eberhard, D. M., G. F. Simons, and C. D. Fennig. 2022. Ethnologue: Languages of the world. 25th ed. Dallas: SIL International.

    A widely known volume set and database on the languages of the world maintained by the evangelical nonprofit organization SIL International, the Ethnologue displays a list of eighty-eight languages classified as language isolates. The lower number compared to other sources shows that Ethnologue is more liberal in accepting proposed genealogical classifications.

  • Georg, S., ed. 2015. Language isolates. London: Routledge.

    A four-volume collection of previously published articles on language isolates that is organized on a geographical basis, with Part 1 focusing on Europe, Part 2 on the Ancient Near East, Part 3 on South Asia, Part 4 on North Asia, Part 5 on Africa, Part 6 on the Americas, and Part 7 on the languages of Australia and the Pacific. Coverage of Eurasia is much more exhaustive than for the Americas and the Pacific.

  • Hammarström, Harald, Robert Forkel, Martin Haspelmath, and Robert Forkel. 2022. Glottolog 4.6. Leipzig: Max Planck Institute for Evolutionary Anthropology.

    A comprehensive catalogue of the world’s languages and associated sources that takes a conservative approach to language classification and, in version 4.6., lists 182 language isolates and their associated primary descriptive sources. Continuously updated.

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