Existential means relating to human existence and experience.
[formal]
Existential questions requiring religious answers still persist.
2. adjective [ADJECTIVE noun]
You use existential to describe fear, anxiety, and other feelings that are caused by thinking about human existence and death.
[formal]
'What if there's nothing left at all?' he cries, lost in some intense existentialangst.
existential in British English
(ˌɛɡzɪˈstɛnʃəl)
adjective
1.
of or relating to existence, esp human existence
2. philosophy
pertaining to what exists, and is thus known by experience rather than reason; empirical as opposed to theoretical
3. logic
denoting or relating to a formula or proposition asserting the existence of at least one object fulfilling a given condition; containing anexistential quantifier