early 15c., from Latin extinctus/exstinctus, past participle of extinguere/exstinguere (see extinguish). Originally of fires; the sense of the condition of "dying out" of a family or a hereditary title, 1580s; of species by 1768. Cf. extinction.
Having no living members. Species become extinct for many reasons, including climate change, disease, destruction of habitat, local or worldwide natural disasters, and development into new species (speciation). The great majority of species that have ever lived—probably more than 99 percent—are now extinct.
No longer active or burning, as an extinct volcano.