You actuéis of actuaractuar v. intr.1 perform an action, to behave in a certain way: in that situation, he did not know how actuar.2 make a person or thing of their nature or, a person acts, features characteristic of a trade or a charge: Earth acts as if it were a magnet whose poles are oriented in the North-South direction; He acted as lawyer defensor.3 represent a role or perform a function, especially in a film or play: one of the singers could not act because of the gripe.4 produce a substance that is effect: this drug acts quickly.
