Is there a single verb that means become extinct?
I have found
vanish, but I think they don't mean exactly the same as become extinct.
"Die out" and "die off" are commonly used in active-voice sentences, where "become extinct" is used in passive-voice sentences.
If the entire species that goes extinct is often referred to using a singular noun, "die" can be used by itself. For example, "The buggy whip industry nearly died in the early twentieth century."
Another way to express that an entire category of people or things "became extinct" is to state that the "last" such person or thing "died". For example, "The last sauropod died 65 million years ago."
The original poster is correct that "disappear" and "vanish" are often used to mean "die out", but (unless the context is very clear) can also mean "become invisible" or "hide" instead.
This answer relates to a single-word verb rather than to a verbal phrase.
A verb would be highly unusual. As a verb, somebody or something has to do something to somebody or something. There needs to be an agent of some kind.
A meteor extinguished the dinosaurs.
It's assumed from context that this means a meteor was responsible for killing all the dinosaurs rather than just a specific group of individuals.
But the meaning isn't explicitly understood without this context. And without context, we would have to add more qualifiers to make it clear it referred to the entire species:
A meteor extinguished all of the dinosaurs that existed.
A meteor extinguished the race of dinosaurs.
I cannot think of a verb that means to kill every member of a species without having to resort to some kind of context or qualification.
There is the noun genocide and the adjective genocidal:
It committed genocide on dinosaurs.
It was a genocidal act against dinosaurs.
But neither of those are verbal. It's not possible to say, for instance:
It genocided dinosaurs.
(Although, in theory, if it were used as a verb, the meaning would be understood.)
The word suicide can be used as a verb. So, although uncommon, it's possible to say:
: to commit suicide
: to put (oneself) to death
But not only would this mean that the species killed itself, which would be highly unusual, but we'd have the same problem of having to qualify the noun so as to make it clear that it was every member of the race that was referenced rather than just an individual or a few specific members.
The verb die is, of course, possible. But it, too, would require context or qualification so as to make it clear that it was referencing an entire species. (It doesn't carry that connotation as part of its own definition.)
In short, there is no actual single-word verb I can think of that expresses this concept.
That leaves verbal phrases (such as killed off or died off), which may also have to be used in context or with some kind of qualification, single-word nouns or adjectives rather than actual verbs, or a coined verbal use of genocide.
You might consider defunct as presented in this link.