What is the origin of existential?
Existential comes from Late Latin existentiālis “relating to existence,” an adjective form of ex(s)istentia “existence, state of existing, something that exists.” Ex(s)istentia is in turn based on classical Latin ex(s)istere “to exist, appear, emerge,” a verb composed of the prefix ex- “out of” and sistere “to stand, cause to stand, stop, set up.” In its first sense “of or relating to existence,” as in “The economic downturn posed an existential threat to small businesses,” existential is recorded in English in the mid-1600s. The second sense of existential, “of, relating to, or characteristic of philosophical existentialism; concerned with the nature of human existence as determined by the individual’s freely made choices,” is found by the late 1800s. Existentialism comes from German Existentialismus, coined in 1919. It is a movement closely associated with such philosophers as Jean-Paul Sartre and Martin Heidegger, and stresses the individual’s unique position as a self-determining agent responsible for making meaningful, authentic choices in a universe seen as purposeless or irrational.