The term 'Operation Reminder' is a crossword solution that can be abbreviated to the four-letter word SCAR. Operation Reminder was a civil rights demonstration in the 1950s and 1960s, organized by the NAACP, which sought to challenge racial segregation in the United States. The demonstration involved African Americans marching in protest of segregation laws, and it was met with violence from white supremacists. The name 'Operation Reminder' was chosen to remind people of the importance of civil rights and the need to fight for them.