The phrase "be whipping boy" refers to being a scapegoat or taking the blame for someone else's mistakes or wrongdoings. Synonyms for this phrase include being the fall guy, the sacrificial lamb, or the scapegoat. Similar phrases may include being thrown under the bus, taking the rap, or being blamed/accused unjustly. These terms are often used in situations where someone is unfairly blamed or punished for a situation that they did not cause or have any control over, and it is important to recognize and address these instances to promote fairness and justice.