Existential threat

I have never used the word "existential" except to quote someone else. I don't have any idea what it means when others use it. So, I looked it up and here's what Britannica Editor said: It's used 3 ways,

 
"existential threat
existential questions
existential crisis

The first phrase, existential threat, is used in texts or discussions about politics, usually politics in the Middle East. In this context, existential is being used literally. An existential threat is a threat to a people’s existence or survival.

The second phrase, existential questions, references Existentialism, a 20th century philosophy concerned with questions about how and whether life has meaning, and why we exist. (For more information, look up Existentialism or the philosopher, Jean-Paul Sartre.)

The third phrase, existential crisis, is also a reference to Existentialism, but it is often used in a humorous or sarcastic way, to suggest that the person or people being described spend too much thinking about themselves and the meaning of their lives.

In sum, existential can be a reference to survival, or to the meaning of our lives, or used to poke fun at others who might take themselves a bit too seriously."

Hmm. I probably still won't use the word. But I will say, it is overused and overrated.