relatedlanguages

Related languages are languages that descend from a common ancestral language, forming a language family. The most general level is the family; subdivisions are branches and subgroups, such as Romance, Germanic, or Slavic within the Indo-European family. Linguists establish relatedness primarily through the comparative method, examining systematic sound correspondences, shared basic vocabulary (cognates), and convergences in grammar and core syntax. They distinguish genetic relatedness from contact-induced similarities or areal features seen in Sprachbund regions.

Romance languages (Spanish, French, Italian, Portuguese, Romanian) evolved from Latin and share many core features while maintaining distinct histories. Germanic languages (German, Dutch, Swedish, English) show common developments such as regular sound changes and shared vocabularies. Slavic languages (Russian, Polish, Czech) likewise descend from Proto-Slavic and exhibit systematic correspondences in phonology and morphology. Language ancestry is often traced to a single proto-language, such as Proto-Indo-European, reconstructed by linguists using the comparative method.

Degrees of relatedness range from broad families to smaller subgroups; isolates are languages with no demonstrable living relatives. Mutual intelligibility is not a reliable measure of relatedness; closely related languages may be difficult to understand, and distant languages can influence one another through borrowing. In some regions, contact and language convergence create areal features that obscure genetic relationships. Related languages illuminate history, migration, and cultural contact, and the field relies on careful reconstruction, documentation, and comparative analysis.