diachrony
Linguistics term referring to the study of language change over time; often contrasted with 共時 (synchrony).
See also: 共時
Diachronic linguistics is the field that studies historical changes in language.
This paper analyzes grammaticalization from a diachronic perspective.
diachronic
diachronic linguistics
Compound of 通 (through, across) and 時 (time), literally 'through time', used as a technical term in linguistics for diachronic study.