Language isolateA language isolate is a language that has no demonstrable genetic relationship with another language. Basque in Europe, Ainu in Asia, Sandawe in Africa, Haida in North America, Kanoê in South America, and Tiwi in Australia are all examples of language isolates. The exact number of language isolates is yet unknown due to insufficient data on several languages. One explanation for the existence of language isolates is that they might be the last remaining branch of a larger language family.
Areal featureIn geolinguistics, areal features are elements shared by languages or dialects in a geographic area, particularly when such features are not descended from a proto-language, or, common ancestor language. That is, an areal feature is contrasted to lingual-genealogically determined similarity within the same language family. Features may diffuse from one dominant language to neighbouring languages (see "sprachbund"). Genetic relationships are represented in the family tree model of language change, and areal relationships are represented in the wave model.
Tree modelIn historical linguistics, the tree model (also Stammbaum, genetic, or cladistic model) is a model of the evolution of languages analogous to the concept of a family tree, particularly a phylogenetic tree in the biological evolution of species. As with species, each language is assumed to have evolved from a single parent or "mother" language, with languages that share a common ancestor belonging to the same language family.
Wave modelIn historical linguistics, the wave model or wave theory (German Wellentheorie) is a model of language change in which a new language feature (innovation) or a new combination of language features spreads from its region of origin, affecting a gradually expanding cluster of dialects. Dialect diffusion spreads from a given point of contact like waves on the water. The theory was intended as a substitute for the tree model, which did not seem to be able to explain the existence of some features, especially in the Germanic languages, by descent from a proto-language.
Koreanic languagesKoreanic is a small language family consisting of the Korean and Jeju languages. The latter is often described as a dialect of Korean, but is distinct enough to be considered a separate language. Alexander Vovin suggests that the Yukjin dialect of the far northeast should be similarly distinguished. Korean has been richly documented since the introduction of the Hangul alphabet in the 15th century. Earlier renditions of Korean using Chinese characters are much more difficult to interpret.
SprachbundA sprachbund (ˈsprɑːkbʊnd ˈʃpʁaːxbʊnt, lit. "language federation"), also known as a linguistic area, area of linguistic convergence, or diffusion area, is a group of languages that share areal features resulting from geographical proximity and language contact. The languages may be genetically unrelated, or only distantly related, but the sprachbund characteristics might give a false appearance of relatedness. A grouping of languages that share features can only be defined as a sprachbund if the features are shared for some reason other than the genetic history of the languages.
Language familyA language family is a group of languages related through descent from a common ancestral language or parental language, called the proto-language of that family. The term "family" reflects the tree model of language origination in historical linguistics, which makes use of a metaphor comparing languages to people in a biological family tree, or in a subsequent modification, to species in a phylogenetic tree of evolutionary taxonomy. Linguists therefore describe the daughter languages within a language family as being genetically related.
Sino-Tibetan languagesSino-Tibetan, also cited as Trans-Himalayan in a few sources, is a family of more than 400 languages, second only to Indo-European in number of native speakers. The vast majority of these are the 1.3 billion native speakers of Sinitic languages. Other Sino-Tibetan languages with large numbers of speakers include Burmese (33 million) and the Tibetic languages (6 million). Other languages of the family are spoken in the Himalayas, the Southeast Asian Massif, and the eastern edge of the Tibetan Plateau.
Linkage (linguistics)In historical linguistics, a linkage is a network of related dialects or languages that formed from a gradual diffusion and differentiation of a proto-language. The term was introduced by Malcolm Ross in his study of Western Oceanic languages . It is contrasted with a family, which arises when the proto-language speech community separates into groups that remain isolated from each other and do not form a network. Linkages are formed when languages emerged historically from the diversification of an earlier dialect continuum.
Comparative linguisticsComparative linguistics is a branch of historical linguistics that is concerned with comparing languages to establish their historical relatedness. Genetic relatedness implies a common origin or proto-language and comparative linguistics aims to construct language families, to reconstruct proto-languages and specify the changes that have resulted in the documented languages. To maintain a clear distinction between attested and reconstructed forms, comparative linguists prefix an asterisk to any form that is not found in surviving texts.