Yes, act is a Scrabble word!

Verb

1. Perform an action, or work out or perform (an action)

2. Behave in a certain manner; show a certain behavior; conduct or comport oneself

3. Play a role or part

4. Discharge one's duties

5. Pretend to have certain qualities or state of mind

6. Be suitable for theatrical performance

7. Have an effect or outcome; often the one desired or expected

8. Be engaged in an activity, often for no particular purpose other than pleasure

9. Behave unnaturally or affectedly

10. Perform on a stage or theater

Noun

1. A legal document codifying the result of deliberations of a committee or society or legislative body

2. Something that people do or cause to happen

3. A subdivision of a play or opera or ballet

4. A short theatrical performance that is part of a longer program

5. A manifestation of insincerity