1. past tense and past participle of act; performed an action or behaved in a specified way
2. performed in a play, movie, or other dramatic production
3. served temporarily in a position or role

Examples

• She acted quickly when she saw the emergency.
• He acted strangely after receiving the news.
• The famous actor acted in several Broadway shows.
• She acted the part of Lady Macbeth brilliantly.
• He acted as chairman while the regular chairman was away.
• The medicine acted fast to reduce her fever.
• They acted on the advice of their lawyer.