1Pure action, unmixed with potentiality or passivity; an instance of this.
Frequently used by Scholastic philosophers to describe God.
2A mental act uncontaminated by elements of sensory awareness.
Late 16th century; earliest use found in Stephen Gosson (bap. 1554, d. 1625), anti-theatrical polemicist and Church of England clergyman. From post-classical Latin actus purus pure act from classical Latin āctus + pūrus, after ancient Greek ἐνέργεια.