Put on an act is a phrase used to describe a situation where someone pretends to be someone or something they are not. Some synonyms for this phrase include playing a role, putting up a façade, pretending, acting, feigning, simulating, faking, and masquerading. These words are often used in situations where an individual is trying to deceive others by acting out a different persona. Whether it's on stage or in everyday life, many people find themselves needing to put on an act to get the results they want. No matter what word you choose to describe the act, it's important to remember that honesty is always the best policy.