The idiom "take the fifth" means to refuse to answer a question or give information in order to avoid incriminating oneself. It comes from the Fifth Amendment of the United States Constitution, which gives citizens the right to remain silent and not incriminate themselves in a criminal trial.
You would use this idiom when someone is being questioned or interrogated and they do not want to answer a question that could potentially get them in trouble. For example, if a police officer asks a suspect if they were involved in a crime, the suspect may "take the fifth" and refuse to answer the question in order to avoid self-incrimination.
In everyday conversation, people may also use this idiom to indicate that they do not want to discuss a certain topic or answer a particular question. For instance, if someone asks about your personal life and you don't want to share certain details, you could say "I'm going to take the fifth on that one."
• During the trial, the defendant's lawyer advised him to take the fifth and not answer any questions that may incriminate him.
• The journalist refused to reveal his sources and took the fifth when asked about his information.
• I don't want to talk about my grades, I will take the fifth.
• When the police asked him where he was on the night of the crime, he decided to take the fifth.
• The politician was questioned about his involvement in the scandal and he chose to take the fifth instead of answering the questions.
• After consulting with his legal team, the CEO decided to take the fifth and not testify in the investigation.