comparative linguistics
noun /kəmˌpærətɪv lɪŋˈɡwɪstɪks/
/kəmˌpærətɪv lɪŋˈɡwɪstɪks/
[uncountable]- the study of how related languages are similar and different, especially in order to discover things about a language that both these languages came from, and that no longer exists