Jack Ruby, an infamous figure in American history, is synonymous with the assassination of Lee Harvey Oswald, the alleged assassin of President John F. Kennedy. Ruby, originally known as Jacob Rubenstein, gained notoriety for his shocking act of shooting Oswald in the basement of the Dallas Police Headquarters in 1963. Often referred to as a nightclub owner, Ruby was also associated with organized crime. Synonyms for Jack Ruby include assassin, killer, murderer, and perpetrator. Ruby's actions on that fateful day continue to fascinate conspiracy theorists and remain a pivotal moment in the turbulent era of the 1960s.