Adjective

1. Temporarily assuming the duties or authority of another person when they are unable to do their job.

   The Acting Minister must sign Executive Council documents in a Minister's absence.

   Acting President of the United States is a temporary office in the government of the United States.

Noun

1. An intended action or deed.
2. Pretending.
3. The occupation of an actor.
4. The deeds or actions of parties are called actings to avoid confusion with the legal senses of deeds and actions.