The term "Joseph McCarthy" refers not to a common English word, but to a specific person in American history. Here is a simple explanation for a new English learner:
Joseph McCarthy (1908-1957) was a politician in the United States, specifically a senator. He is known for making serious accusations against many people, claiming that they were communists or had ties to communism. His actions are often seen as unfair and harmful, as he accused many innocent people without solid evidence.
"During the Cold War, Joseph McCarthy became famous for his aggressive investigations into suspected communists."
In discussions about politics, history, or civil rights, people might refer to "McCarthyism," which describes the practice of making accusations without proper evidence, similar to what McCarthy did.
Joseph McCarthy is an important figure in American history, particularly noted for his role in the Red Scare and the fear of communism during the 1950s.