Related to diachronic linguistics: historical linguistics, synchronic linguistics,

To better mark that opposition and crossing between two orders of phenomena relative to the same object, we prefer to speak of synchronic linguistics and diachronic linguistics.

Monique Dufresne: Diachronic linguistics; syntax & morphology of medieval French; history of French; creation and use of annotated corpora.

Diachronic linguistics studies the relations which hold not between the coexisting terms of a linguistic state, but between successive terms substituted one for another over a period of time.

Diachronic linguistics studies the relations which hold not between the coexisting terms of a linguistic state, but between successive terms substituted one for another over a period of time.