Entelechy
One of Marginalia’s Fragments of the Old Web 🔗 is a small site called Ragged Entelechy 🔗 by Fiona Webster. From the site:
An entelechy is that which realizes or makes actual, what is otherwise merely potential.
Britannica’s entelechy page 🔗 seems to explain it as the thing which which turns the physical matter of a human or a chair or so on into the complete, realised human or chair or so on, like a “soul”.
Judging from the Britannica page, “entelechy” probably isn’t a word which is generally usable outside of Aristotelian metaphysics, although I do wonder if, for example, pushing a boulder down a hill and converting its potential energy to kinetic energy makes you that energy’s entelechy.