Telos

Etymology

Greek "telos" meant end, completion, or purpose. Aristotle made it central to his thought: everything has a telos, the function it exists to fulfill. It powers "teleology," explanation by purpose, and hides inside "entelechy."

noun · /TEL-oss/
The end, goal, or built-in purpose toward which something is directed.
What it names
It gives a single handle for the "what it is for" of a thing, as distinct from what merely caused it.
Example
He asked what the telos of the university actually was — to certify workers, to seek truth, or to sort the young by class.
Related idea
The root beneath teleology; to ask a thing’s telos is to ask what it is for, not what pushed it into being.