acting

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 take action in a situation. The report is due tomorrow, so I need you to act on it immediately. Please act upon this subpoena for records at once.

2. To take action that is strongly influenced by certain information or advice. ("Upon" is most commonly used to convey this meaning.) Acting upon my doctor's orders, I cleared my schedule and spent the week recuperating at home. A; "I can't believe he said that about us!" B: "Well, he's probably just acting on his mother's instruction, and that woman hates us."

3. To impact in some way. The barking dogs next door are acting on my patience.

1. To behave poorly or inappropriately, especially considering one's age. My son is always so happy at home, so I can't understand why he's suddenly acting out at school. You're in middle school now, so if you act out in class, you will be sent to the principal's office.

2. To perform a role, often an imaginary one (as in a play). Jennifer did a superb job acting out the role of Auntie Mame in the play. I don't want to upset my mom during the holidays, so I am acting out the part of dutiful daughter.

3. To express one's negative feelings, usually to another person. I got tired of Mark constantly acting out his anger out on me, so I ended our relationship.

4. To communicate through actions or gestures instead of words. Henry was suffering from a severe case of laryngitis and had lost his voice, so he had to act out his thoughts during the meeting. There's no talking in this game—you have to act out the movie you're assigned, and we will try to guess it.

1. To behave comically or playfully, often to amuse others. If you continue to act the fool, you're going to have to leave the classroom. Joe never acts the fool—he's always serious.

2. To behave irresponsibly or immaturely, especially in an environment where it is especially inappropriate. Don't let me catch any of you kids acting the fool at the museum—it's a privilege to even go inside. We finally get invited to a nice dinner party and you have to go and act the fool—what's wrong with you?

1. Of a person, to behave poorly or inappropriately. If you act up in class, you will be sent to the principal's office.

2. Of a thing, to malfunction or operate incorrectly. My car's transmission started acting up during my commute to work. My phone acted up again this morning; I think I need to take it to a professional.

3. Of a medical condition, to become problematic or troublesome, usually after a period of remission. Jake played football with his friends today, and now his old knee injury is acting up. It's springtime, so of course my allergies are acting up again.

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.

1. to perform in real life a role that one has imagined in a fantasy. When I was onstage, I was really acting an old fantasy out. I acted out an old fantasy onstage.

2. to convert one's bad feelings into action rather than words. Don't act your aggressions out on me! She acted out her aggression.

3. to demonstrate or communicate something through gestures or action rather than words. Act your request out, if you can't say it. She had a sore throat and had to act out her request.

1. to behave badly Sometimes kids act up because they just want attention.

2. to operate badly My computer began acting up and I lost a whole day's work.

3. to become active Her allergies acted up when she went hiking in the woods.

1. Perform or portray something or someone, as in As she read to the class, the teacher had each child act out a different character in the story . [c. 1600]

2. Express unconscious feelings or impulses through one's behavior, without being aware of it. For example, She acted out her anger at her father by screaming at her husband. This meaning comes from 20th-century psychological theory and usually (but not always) refers to negative or hostile impulses and emotions. The term is sometimes used without an object to mean "misbehave" or "behave disruptively," as in The child is acting out in class. [First half of 1900s] In both usages, out means "openly" or "publicly."

1. Misbehave. For example, With an inexperienced rider, this horse always acts up. [c. 1900]

2. Malfunction, as in I'm not sure what's wrong with my car, but the transmission is acting up. In both usages up means "abnormally."