Abstract
<jats:p>Language obsolescence and language death are potential outcomes of language shift – itself a potential outcome of language contact. Language shift, obsolescence, and death are of critical importance to linguistics today given the massive global endangerment of minority languages. These topics are also critically important to diachronic linguistics as the study of languages over time helps us to understand the reasons for and outcomes of these processes. Further, looking at these processes over time provides the necessary depth in understanding new situations of language shift, obsolescence, and death and for understanding the changes to the grammar and the verbal repertoire across the lifespan and across generations. Language shift, obsolescence, and death are like other forms of diachronic linguistic change to the extent that they represent orderly variation across speakers within a speech community with proficiency levels varying, though changes to the linguistic structure and the verbal repertoire allow for full discussion of the processes taking place. Thus, language shift, obsolescence, and death are not only exclusively centered on structural linguistic change over time, but also tightly connected with and determined by socially determined language change over time.</jats:p>