actus

noun

ac·​tus

ˈak-təs,

especially in sense 2 ˈäk-ˌtu̇s

plural actus

1

Roman law : the right to drive a beast or a vehicle over another's land

—distinguished from iter and via

2

[Medieval Latin (translation of Greek energeia), from Latin actus] : an act or thing done

specifically : a mental or spiritual act

—used in Scholasticism to render Aristotle's terms energeia and entelecheia compare energy, entelechy

Word History

Etymology

Latin, literally, driving, doing, act, deed

First Known Use

1812, in the meaning defined at sense 1

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