define historical linguistics
Historical linguistics, also called diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include: 1  to describe and account for observed changes in particular languages. 2  to reconstruct the pre-history of languages and to determine their relatedness, grouping them into language families (comparative linguistics).
Linguistics is the scientific study of language. There are three aspects to this study: language form, language meaning, and language in context.inguistics also includes nonformal approaches to the study of other aspects of human language, such as social, cultural, historical and political factors.