What do we call the original language from which various daughter languages develop?

The term that refers to the original language from which various daughter languages develop is known as a protolanguage. Protolanguages are the hypothetical common ancestors of language families. Linguists reconstruct these languages through the comparison of the phonetic, grammatical, and lexical similarities among languages that are believed to have descended from the same source.

This concept is fundamental in historical linguistics, as it allows researchers to trace the development and diversification of languages over time. By identifying the core features of a protolanguage, linguists can better understand the evolution of its related languages, which help in reconstructing aspects of ancient cultures that spoke these languages.

The other terms have distinct meanings that do not pertain to the concept of an original language from which other languages evolve. Dialects refer to variations of a language that can exist within a single language framework but do not imply a separate origin. Creole languages arise from the mixing of languages, usually in the context of colonization and are distinct from the protolanguages they might have originated from. A substrate is a linguistic term that describes the influence of a native language on a new language that occurs among speakers during language change or contact, again falling outside the definition of an original language.