Under this definition, a language becomes extinct upon the death of its last native speaker, the terminal speaker.

A language like Latin is not extinct in this sense, because it evolved into the modern Romance languages; it is impossible to state when Latin became extinct because there is a diachronic continuum (compare synchronic continuum) between ancestors Late Latin and Vulgar Latin on the one hand and descendants like Old French and Old Italian on the other; any cutoff date for distinguishing ancestor from descendant is arbitrary.

For many languages which have become extinct in recent centuries, attestation of usage is datable in the historical record, and sometimes the terminal speaker is identifiable.

In other cases, historians and historical linguists may infer an estimated date of extinction from other events in the history of the sprachraum.

with the death of Edna Campbell Guerrero [311]