1. To be a representative for someone else. Because I have power of attorney for my mother, I can act for her in legal and financial matters when she is no longer able to do so.
2. To perform a job or role in place of the person that usually does it. Yes, Kayla usually leads this project, but I am acting for her while she is on maternity leave.
1. to represent someone in an official capacity; to represent the interests of someone. Don't worry. I am acting for the owner. I am his real estate agent.
2. to take action when the proper person fails to take action. I had to act for her since she was out of town.