1.
A species of animal or plant that is extinct no longer has any living members, either in the world or in a particular place.
It is 250 years since the wolf became extinct in Britain.
ADJ
2.
If a particular kind of worker, way of life, or type of activity is extinct, it no longer exists, because of changes in society.
Herbalism had become an all but extinct skill in the Western world.
ADJ
3.
An extinct volcano is one that does not erupt or is not expected to erupt any more.
Its tallest volcano, long extinct, is Olympus Mons.
ADJ