Entelechy

entelechy \en-ˈte-lə-kē, in-\ noun: 1. (according to Aristotle) the condition of something whose essence is fully realized, 2. (in some modern philosophical systems) a vital force that motivates and guides an organism toward self-fulfillment

Etymology: Late Latin entelechia, from Greek entelecheia, from entelēs complete (from en- in, within + telos end) + echein to have

For more information, see Wikipedia’s article on entelechy.